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Sample records for anticancer quinolone derivative

  1. Voreloxin is an anticancer quinolone derivative that intercalates DNA and poisons topoisomerase II.

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    Rachael E Hawtin

    Full Text Available BACKGROUND: Topoisomerase II is critical for DNA replication, transcription and chromosome segregation and is a well validated target of anti-neoplastic drugs including the anthracyclines and epipodophyllotoxins. However, these drugs are limited by common tumor resistance mechanisms and side-effect profiles. Novel topoisomerase II-targeting agents may benefit patients who prove resistant to currently available topoisomerase II-targeting drugs or encounter unacceptable toxicities. Voreloxin is an anticancer quinolone derivative, a chemical scaffold not used previously for cancer treatment. Voreloxin is completing Phase 2 clinical trials in acute myeloid leukemia and platinum-resistant ovarian cancer. This study defined voreloxin's anticancer mechanism of action as a critical component of rational clinical development informed by translational research. METHODS/PRINCIPAL FINDINGS: Biochemical and cell-based studies established that voreloxin intercalates DNA and poisons topoisomerase II, causing DNA double-strand breaks, G2 arrest, and apoptosis. Voreloxin is differentiated both structurally and mechanistically from other topoisomerase II poisons currently in use as chemotherapeutics. In cell-based studies, voreloxin poisoned topoisomerase II and caused dose-dependent, site-selective DNA fragmentation analogous to that of quinolone antibacterials in prokaryotes; in contrast etoposide, the nonintercalating epipodophyllotoxin topoisomerase II poison, caused extensive DNA fragmentation. Etoposide's activity was highly dependent on topoisomerase II while voreloxin and the intercalating anthracycline topoisomerase II poison, doxorubicin, had comparable dependence on this enzyme for inducing G2 arrest. Mechanistic interrogation with voreloxin analogs revealed that intercalation is required for voreloxin's activity; a nonintercalating analog did not inhibit proliferation or induce G2 arrest, while an analog with enhanced intercalation was 9.5-fold more

  2. Synthesis and anticancer activity of novel curcumin-quinolone hybrids.

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    Raghavan, Saiharish; Manogaran, Prasath; Gadepalli Narasimha, Krishna Kumari; Kalpattu Kuppusami, Balasubramanian; Mariyappan, Palanivelu; Gopalakrishnan, Anjana; Venkatraman, Ganesh

    2015-09-01

    A number of new curcumin-quinolone hybrids were synthesised from differently substituted 3-formyl-2-quinolones and vanillin and their in vitro cytotoxicity was determined on a panel of representative cell lines (A549, MCF7, SKOV3 and H460) using MTT assay. The most potent compound 14, was analysed for its mode of action using various cell biology experiments. SKOV3 cells treated with compound 14 showed distorted cell morphology under phase contrast imaging and induction of apoptosis was confirmed by Annexin V/PE assay. Further experiments on generation of reactive oxygen species (ROS) and cell cycle analysis revealed that these hybrids induce apoptosis by ROS generation and arrest cell cycle progression in S and G2/M phase.

  3. Synthesis and Antimicrobial Activity of some Tetrahydro Quinolone Diones and Pyrano[2,3-d]pyrimidine Derivatives

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    Shahi, Masoume; Foroughifar, Naser; Mobinikhaledi, Akbar

    2015-01-01

    There has been special interest in the chemistry of quinolone and pyrimidine derivatives due to their diverse biological activities such as anticonvulsant, anti-malarial agents, antibacterial, antiviral, cytostatic, antithelemintic, antigenotoxic, anti-cancer agents. These compounds are also used as targeting delayed-type hypersensivity and anti-convulsant agents. As a part of our research works in the synthesis of pyrimidine derivatives containing biological activities, a series of novel pyrano[2,3-d]pyrimidine derivatives 2 and tetrahydro quinolone dione derivatives 3 were synthesized via reaction of tetrahydrobenzo[b]pyrano derivatives 1 with different reagents in suitable yields. The characterization of these synthesized compounds was established by IR, 1H NMR and 13C NMR spectroscopic data. Furthermore, all compounds were subsequently evaluated for their in-vitro antibacterial activity against three bacteria: Staphylococcus aureus (ATTC-25923), Escherichia Coli (ATTC-25922) and Bacillus anthracic (ATTC-25924). PMID:26330864

  4. Synthesis, characterization of some novel 1,3,4-oxadiazole compounds containing 8-hydroxy quinolone moiety as potential antibacterial and anticancer agents

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    Vinayak Mahadev Adimule

    2014-12-01

    Full Text Available In the present work a series of novel derivatives of 8-hydroxy quinolone substituted 1,3,4-oxadiazole compounds were synthesized by convergent synthetic method and studied for their antibacterial and anticancer properties. The cell lines used for cytotoxic evaluation were HeLa, Caco-2 and MCF7. The synthetic chemistry involved conversion of various substituted aromatic acids into ethyl ester 2a-e. The ethyl ester was converted into corresponding carbohydrazide 3a-e. Carbohydrazides are reacted with chloroacetic acid, phosphorous oxytrichloride and irradiated with microwave in order to obtain the various key intermediates 2-(chloromethyl-5-(substituted phenyl-1,3,4-oxadiazole 4a-e. The 2-(chloromethyl-5-(substituted phenyl-1,3,4-oxadiazole was reacted with 8-hydroxy quinolone in presence of sodium hydride and obtained a series of 8-hydroxy quinoline substituted 1,3,4-oxadiazoles 5a-e. Among the synthesised compounds, the cytotoxicity of the compound 5b i.e. 8-{[5-(2,4-dichlorophenyl-1,3,4-oxadiazol-2-yl]methoxy}quinoline against MCF7 with IC50 of 5.3µM and the compound 5e i.e. 8-{[5-(4-bromophenyl-1,3,4-oxadiazol-2-yl]methoxy}quinoline showed MIC of < 6.25µg/mL against Staphylococcus aureus which is comparable with the known standards. The standards used for cytotoxic evaluation was 5-fluorouracil and for antibacterial was nitrofurazone

  5. Novel substituted benzothiophene and thienothiophene carboxanilides and quinolones: synthesis, photochemical synthesis, DNA-binding properties, antitumor evaluation and 3D-derived QSAR analysis.

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    Aleksić, Maja; Bertoša, Branimir; Nhili, Raja; Uzelac, Lidija; Jarak, Ivana; Depauw, Sabine; David-Cordonnier, Marie-Hélène; Kralj, Marijeta; Tomić, Sanja; Karminski-Zamola, Grace

    2012-06-14

    A series of new N,N-dimethylaminopropyl- and 2-imidazolinyl-substituted derivatives of benzo[b]thienyl- and thieno[2,3-b]thienylcarboxanilides and benzo[b]thieno[2,3-c]- and thieno[3',2':4,5]thieno[2,3-c]quinolones were prepared. Quinolones were prepared by the reaction of photochemical dehydrohalogenation of corresponding anilides. Carboxanilides and quinolones were tested for the antiproliferative activity. 2-Imidazolinyl-substituted derivatives showed very prominent activity. By use of the experimentally obtained antitumor measurements, 3D-derived QSAR analysis was performed for the set of compounds. Highly predictive 3D-derived QSAR models were obtained, and molecular properties that have the highest impact on antitumor activity were identified. Carboxanilides 6a-c and quinolones 9a-c and 11a were evaluated for DNA binding propensities and topoisomerases I and II inhibition as part of their mechanism of action assessment. The evaluated differences in the mode of action nicely correlate with the results of the 3D-QSAR analysis. Taken together, the results indicate which modifications of the compounds from the series should further improve their anticancer properties.

  6. Synthesis of (-)-arctigenin derivatives and their anticancer activity.

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    Gui-Rong, Chen; Li-Ping, Cai; De-Qiang, Dou; Ting-Guo, Kang; Hong-Fu, Li; Fu-Rui, Li; Ning, Jiang

    2012-01-01

    The natural dibenzylbutyrolactone type lignanolide (-)-arctigenin, which was prepared from fructus arctii, showed obvious anticancer activity. The synthesis of four new (-)-arctigenin derivatives and their anticancer bioactivities were examined. The structures of the four new synthetic derivatives were elucidated.

  7. Chemistry of Nitroquinolones and Synthetic Application to Unnatural 1-Methyl-2-quinolone Derivatives

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    Nagatoshi Nishiwaki

    2010-07-01

    Full Text Available The 1-methyl-2-quinolone (MeQone framework is often found in alkaloids and recently attention was drawn to unnatural MeQone derivatives with the aim of finding new biologically active compounds, however, low reactivity of the MeQone framework prevents the syntheses of versatile derivatives. A nitro group is one of the useful activating groups for this framework that enables a concise chemical transformation. Among nitroquinolones, 1-methyl-3,6,8-trinitro-2-quinolone (TNQ exhibits unusual reactivity favoring region-selective cine-substitutions that afford 4-substituted 1-methyl-6,8-dinitro-2-quinolones upon treatment with nucleophilic reagents. Contrary to this, 1-methyl-3,6-dinitro-2-quinolone (3,6-DNQ does not undergo any reaction under the same conditions. The unusual reactivity of TNQ is caused by steric repulsion between the methyl group at the 1-position and the nitro group at the 8-position, which distorts the MeQone framework. As a result, the pyridone ring of TNQ loses aromaticity and acts rather as an activated nitroalkene. Indeed, the pyridone moiety of TNQ undergoes cycloaddition with electron-rich alkenes or dienes under mild conditions, whereby a new fused ring is constructed on the [c]-face of the MeQone. Consequently, TNQ can be used as a new scaffold leading to versatile unnatural MeQone derivatives.

  8. Design, synthesis and antitumor activity of 3-substituted quinolone derivatives (Ⅰ)

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A series of quinolone derivatives containing benzimidazole, benzoxazole or benzothiazole ring were synthesized. The cytotoxicity of 12 new compounds was evaluated in KB, Be17402, A2780 and HT-29 cell lines. Most of synthesized compounds showed moderate inhibitory activity against cancer cells. The inhibitory activities of 6k, against KB and A2780 tumor cells are comparable to that of topotecan, one of topoisomerase I inhibitors.

  9. Lanthanum triflate triggered synthesis of tetrahydroquinazolinone derivatives of N-allyl quinolone and their biological assessment

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    Jardosh Hardik H.

    2012-01-01

    Full Text Available A series of 24 derivatives of tetrahydroquinazolinone has been synthesized by one-pot cyclocondensation reaction of N-allyl quinolones, cyclic β-diketones and (thiourea/N-phenylthiourea in presence of lanthanum triflate catalyst. This methodology allowed us to achieve the products in excellent yield by stirring at room temperature. All the synthesized compounds were investigated against a representative panel of pathogenic strains using broth microdilution MIC (minimum inhibitory concentration method for their in vitro antimicrobial activity. Amongst these sets of heterocyclic compounds 5h, 6b, 6h, 5f, 5l, 5n and 6g found to have admirable activity.

  10. Synthesis, alkaline phosphatase inhibition studies and molecular docking of novel derivatives of 4-quinolones.

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    Miliutina, Mariia; Ejaz, Syeda Abida; Khan, Shafi Ullah; Iaroshenko, Viktor O; Villinger, Alexander; Iqbal, Jamshed; Langer, Peter

    2017-01-27

    New and convenient methods for the functionalization of the 4-quinolone scaffold at positions C-1, C-3 and C-6 were developed. The 4-quinolone derivatives were evaluated for their inhibitory potential on alkaline phosphatase isozymes. Most of the compounds exhibit excellent inhibitory activity and moderate selectivity. The IC50 values on tissue non-specific alkaline phosphatase (TNAP) were in the range of 1.34 ± 0.11 to 44.80 ± 2.34 μM, while the values on intestinal alkaline phosphatase (IAP) were in the range of 1.06 ± 0.32 to 192.10 ± 3.78 μM. The most active derivative exhibits a potent inhibition on IAP with a ≈14 fold higher selectivity as compared to TNAP. Furthermore, molecular docking calculations were performed for the most potent inhibitors to show their binding interactions within the active site of the respective enzymes.

  11. Anilides and quinolones with nitrogen-bearing substituents from benzothiophene and thienothiophene series: synthesis, photochemical synthesis, cytostatic evaluation, 3D-derived QSAR analysis and DNA-binding properties.

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    Aleksić, Maja; Bertoša, Branimir; Nhili, Raja; Depauw, Sabine; Martin-Kleiner, Irena; David-Cordonnier, Marie-Hélène; Tomić, Sanja; Kralj, Marijeta; Karminski-Zamola, Grace

    2014-01-01

    A series of new anilides (2a-c, 4-7, 17a-c, 18) and quinolones (3a-b, 8a-b, 9a-b, 10-15, 19) with nitrogen-bearing substituents from benzo[b]thiophene and thieno[2,3-c]thiophene series are prepared. Benzo[b]thieno[2,3-c]- and thieno[3',2':4,5]thieno[2,3-c]quinolones (3a-b, 8a-b) are synthesized by the reaction of photochemical dehydrohalogenation from corresponding anilides. Anilides and quinolones were tested for the antiproliferative activity. Fused quinolones bearing protonated aminium group, quaternary ammonium group, N-methylated and protonated aminium group, amino and protonated amino group (8a, 9b, 10-12) showed very prominent anticancer activity, whereby the hydrochloride salt of N',N'-dimethylaminopropyl-substituted quinolone (14) was the most active one, having the IC50 concentration at submicromolar range in accordance with previous QSAR predictions. On the other hand, flexible anilides were among the less active. Chemometric analysis of investigated compounds was performed. 3D-derived QSAR analysis identified solubility, metabolitic stability and the possibility of the compound to be ionized at pH 4-8 as molecular properties that are positively correlated with anticancer activity of investigated compounds, while molecular flexibility, polarizability and sum of hydrophobic surface areas were found to be negatively correlated. Anilides 2a-b, 4-7 and quinolones 3a-b, 8a-b, 9b and 10-14 were evaluated for DNA binding propensities and topoisomerases I/II inhibition as part of their mechanism of action. Among the anilides, only compound 7 presented some DNA binding propensity whereas the quinolones 8b, 9b and 10-14 intercalate in the DNA base pairs, compounds 8b, 9b and 14 being the most efficient ones. The strongest DNA intercalators, compounds 8b, 9b and 14, were clearly distinguished from the other compounds according to their molecular descriptors by the PCA and PLS analysis.

  12. Synthesis and in vitro antibacterial activities of 7-(4-alkoxyimino-3-hydroxypiperidin-1-y1)quinolone derivatives

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A series of novel 7-(4-alkoxyimino-3-hydroxypiperidin-1-yl)quinolone derivatives were designed,synthesized and evaluated for in vitro antibacterial activities.Compounds 8f,8g,8i and 8j with the potencies similar to or better than those of levofloxacin and IMB against Staphylococcus aureus and Staphylococcus epidermidis,worth further investigation.

  13. Anti-cancer activities of diospyrin, its derivatives and analogues

    KAUST Repository

    Sagar, Sunil

    2010-09-01

    Natural products have played a vital role in drug discovery and development process for cancer. Diospyrin, a plant based bisnaphthoquinonoid, has been used as a lead molecule in an effort to develop anti-cancer drugs. Several derivatives/analogues have been synthesized and screened for their pro-apoptotic/anti-cancer activities so far. Our review is focused on the pro-apoptotic/anti-cancer activities of diospyrin, its derivatives/analogues and the different mechanisms potentially involved in the bioactivity of these compounds. Particular focus has been placed on the different mechanisms (both chemical and molecular) thought to underlie the bioactivity of these compounds. A brief bioinformatics analysis at the end of the article provides novel insights into the new potential mechanisms and pathways by which these compounds might exert their effects and lead to a better realization of the full therapeutic potential of these compounds as anti-cancer drugs. © 2010 Elsevier Masson SAS. All rights reserved.

  14. Synthesis and Anticancer Activity of Novel Thiazole-5-Carboxamide Derivatives

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    Wen-Xi Cai

    2016-01-01

    Full Text Available A series of novel 2-phenyl-4-trifluoromethyl thiazole-5-carboxamide derivatives have been synthesized and evaluated for their anticancer activity against A-549, Bel7402, and HCT-8 cell lines. Among the tested compounds, highest activity (48% was achieved with the 4-chloro-2-methylphenyl amido substituted thiazole containing the 2-chlorophenyl group on the two position of the heterocyclic ring. Other structurally similar compounds displayed moderate activity. The key intermediates have been fully characterized.

  15. Novel derivatives of benzo[b]thieno[2,3-c]quinolones: synthesis, photochemical synthesis, and antitumor evaluation.

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    Dogan Koruznjak, Jasna; Grdisa, Mira; Slade, Neda; Zamola, Branimir; Pavelić, Kresimir; Karminski-Zamola, Grace

    2003-10-01

    Novel derivatives of benzo[b]thieno[2,3-c]quinolones 3a-j were synthesized in a multistep synthesis starting from substituted benzo[b]thiophene-2-carbonyl chlorides, to their corresponding benzo[b]thiophene-2-carboxamides, which were photochemically dehydrohalogenated to their corresponding substituted benzo[b]thieno[2,3-c]quinolones. Compound 4 was prepared from 3i by alkylation with 3-dimethylaminopropyl chloride in the presence of NaH. Compounds 7a,b were prepared from 3g in the multistep synthesis from compounds 5 and 6. Compounds 3b, 3c-f, 3h, 7a, and 7b were found to exert cytostatic activity against malignant cell lines: pancreatic carcinoma (MiaPaCa2), breast carcinoma (MCF7), cervical carcinoma (HeLa), laryngeal carcinoma (Hep2), colon carcinoma (CaCo-2), melanoma (HBL), human fibroblast cell lines (WI-38). The compounds that bear a 3-dimethylaminopropyl substituent on the quinolone nitrogen (3b, 3c-f, 3h) showed higher antitumor activity than compounds bearing the same substituent on the amidic nitrogen (7a and 7b). The compound 3h, which has a 3-dimethylaminopropyl substituent on the quinolone nitrogen and a methoxycarbonyl substituent at position 9, had marked antitumor activity. Because of strong cytotoxic effect of compound 4 on melanoma cells (HBL, ME 67.3, and ME 67.1), a potential mechanism of action was examined. Analysis of DNA and Annexin-V-FLUOS staining indicated that compound 4 causes cell death by apoptosis.

  16. Synthesis and anticancer evaluation of alpha-lipoic acid derivatives.

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    Zhang, Shi-Jie; Ge, Qiu-Fu; Guo, Dian-Wu; Hu, Wei-Xiao; Liu, Hua-Zhang

    2010-05-15

    alpha-Lipoic acid derivatives were synthesized and evaluated for their in vitro anticancer activities against NCI-460, HO-8910, KB, BEL-7402, and PC-3 cell lines. The results, for most compounds exhibited dose-dependent inhibitory property and several compounds had good inhibitions at the dose of 100 microg/mL. Compound 17 m was further selected for in vivo evaluation against S180 xenograft in ICR mice, which had 24.7% tumor-weight inhibition through intragastric administration of 200mg/kg of body weight. Moreover, the LD(50) in mice for 17 m through ig exceeded 1000 mg/kg of body weight.

  17. Synthesis of Some Benzimidazole Derivatives Bearing 1,3,4-Oxadiazole Moiety as Anticancer Agents.

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    Mochona, Bereket; Mazzio, Elizabeth; Gangapurum, Madhavei; Mateeva, Nelly; Redda, K K

    2015-04-01

    In an effort to establish new benzimidazole related structural leads with improved anticancer activity, several new benzimidazole derivatives (5a-i) with 1,3,4-oxadiazole scaffold incorporated were synthesized and studied for their anticancer activity. The anticancer screening against MDA-MB-231 breast cancer cell lines showed that compound (5c) exhibited moderate cytotoxicity.

  18. Design, synthesis and biological characterization of a new class of osteogenic (1H)-quinolone derivatives.

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    Manetti, Fabrizio; Petricci, Elena; Gabrielli, Annalisa; Mann, Andrè; Faure, Hélène; Gorojankina, Tatiana; Brasseur, Laurent; Hoch, Lucile; Ruat, Martial; Taddei, Maurizio

    2016-10-04

    Smoothened (Smo) is the signal transducer of the Hedgehog (Hh) pathway and its stimulation is considered a potential powerful tool in regenerative medicine to treat severe tissue injuries. Starting from GSA-10, a recently reported Hh activator acting on Smo, we have designed and synthesized a new class of quinolone-based compounds. Modification and decoration of three different portions of the original scaffold led to compounds able to induce differentiation of multipotent mesenchymal cells into osteoblasts. The submicromolar activity of several of these new quinolones (0.4-0.9 μM) is comparable to or better than that of SAG and purmorphamine, two reference Smo agonists. Structure-activity relationships allow identification of several molecular determinants important for the activity of these compounds.

  19. Synthesis and biological evaluation of 6-fluoro-3-phenyl-7-piperazinyl quinolone derivatives as potential topoisomerase I inhibitors.

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    Ge, Raoling; Zhao, Qian; Xie, Zhouling; Lu, Lu; Guo, Qinglong; Li, Zhiyu; Zhao, Li

    2016-10-21

    The design and synthesis of a new series of 6-fluoro-3-phenyl-7-piperazinyl quinolone derivatives, built on the structure of 1-ethyl-3-(6-nitrobenzoxazol-2-yl)-6,8-difluoro-7-(3-methylpiperazin-1-yl)-4(1H)-quinolone, are described. These compounds provide new scaffold for the discovery of Topoisomerase I (Top I) inhibitors and target based assay showed that they can obviously inhibited Top I at 100 μM. The in vitro anti-proliferative activity of these new compounds was evaluated against A549, Hela, BGC-823, and HepG2 cell lines. Compounds 18a-g showed potent inhibitory activity against the growth of those cancer cell lines. The most positive compounds 18f and 18g demonstrated as potent as camptothecin in Top I inhibition assay and MTT assay. Compounds 18f and 18g led to an obvious increase in the percentage of S phase of the cells in 24 h. The in vivo data showed that 18f and 18g inhibited tumor growth with the inhibitory rate of 29.25% and 42.75% at 20 mg/kg, respectively. The data suggested the therapeutic potential for further development.

  20. Design, synthesis, antibacterial evaluation and docking study of novel 2-hydroxy-3-(nitroimidazolyl)-propyl-derived quinolone.

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    Li, Qing; Xing, Junhao; Cheng, Haibo; Wang, Hui; Wang, Jing; Wang, Shuai; Zhou, Jinpei; Zhang, Huibin

    2015-01-01

    A novel series of 2-hydroxy-3-(nitroimidazolyl)-propyl-derived quinolones 6a-o were synthesized and evaluated for their in vitro antibacterial activity. Most of the target compounds exhibited potent activity against Gram-positive strains. Among them, moxifloxacin analog 6n displayed the most potent activity against Gram-positive strains including S. epidermidis (MIC = 0.06 μg/mL), MSSE (MIC = 0.125 μg/mL), MRSE (MIC = 0.03 μg/mL), S. aureus (MIC = 0.125 μg/mL), MSSA (MIC = 0.125 μg/mL), (MIC = 2 μg/mL). Its activity against MRSA was eightfold more potent than reference drug gatifloxacin. Finally, docking study of the target compound 6n revealed that the binding model of quinolone nucleus was similar to that of gatifloxacin and the 2-hydroxy-3-(nitroimidazolyl)-propyl group formed two additional hydrogen bonds.

  1. Synthesis and in-vitro antibacterial activity of N-piperazinyl quinolone derivatives with 5-chloro-2-thienyl group

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    2008-08-01

    Full Text Available Background and the purpose of the study: Fluoroquinolones are an important group of antimicrobial agents that are used widely in the treatment of various infectious diseases. The purpose of the present study was to synthesize new N-piperazinyl quinolone derivatives with 5-chloro-2-theinyl group having possible antimicrobial activity. Methods: Reaction of ciprofloxacin (1, norfloxacin (2 and enoxacin (3 with α-bromoketone 10 or α-bromooxime derivatives 11a-c in DMF, in the presence of NaHCO3 at room temperature, afforded corresponding ketones 4a-c or oxime derivatives 5-7(a-c, respectively. Results and major conclusion: The synthesized compounds were tested against a series of Gram-positive and Gram-negative bacteria. The results of MIC tests against both Gram-positive and Gram-negative bacteria revealed that ciprofloxacin derivatives (compounds 4a, 5a, 6a and 7a were more active than norfloxacin and enoxacin analogues. Compound 5a, containing N-[2-(5-chlorothiophen-2-yl-2-hydroxyiminoethyl] residue provided a high in vitro antibacterial activity against Gram-positive bacteria, with MIC of 0.06, 0.125, 0.5 and 0.125 μg/mL against S. aureus, S. epidermidis, E. feacalis and B. subtilis, respectively. Its activity was found to be 4 to 8 times better than reference drug (ciprofloxacin against all Gram-positive bacteria with the exception of E. feacalis.

  2. In vitro evaluation of anticancer effect and neurotoxicity of Styrylpyrone derivative (SPD)

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    Yip, Chee-Wai; Nagaoka, Yasuo; Nor, Norefrina Shafinaz Md.; Ibrahim, Nazlina

    2016-11-01

    The increasing number of death due to cancer emphasizes the need of novel anticancer agents. Styrylpyrone derivative (SPD) was previously found to have potential anticancer action towards many types of cancer. Some of the SPD-anticancer mechanisms were elucidated as induction of cancer cell apoptosis. However, more understanding on cancer cell type specific action of SPD-anticancer effects needs to be evaluated. HCT-116 cell line, a type of human colon carcinoma, was used to study SPD-anticancer effect. It was found that SPD concentration as low as 0.25 µM was able to inhibit 80% growth of cancer cells. IC50 value of SPD for HCT-116 was found to be 0.038 µM. Neurotoxicity test, carried out to determine the adverse effect of SPD towards nerve cells, gives CC50 value as 4.88 µM, thus concluded it to be a neurotoxic compound.

  3. Glutamic acid and its derivatives: candidates for rational design of anticancer drugs.

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    Ali, Imran; Wani, Waseem A; Haque, Ashanul; Saleem, Kishwar

    2013-05-01

    Throughout the history of human civilizations, cancer has been a major health problem. Its treatment has been interesting but challenging to scientists. Glutamic acid and its derivative glutamine are known to play interesting roles in cancer genesis, hence, it was realized that structurally variant glutamic acid derivatives may be designed and developed and, might be having antagonistic effects on cancer. The present article describes the state-of-art of glutamic acid and its derivatives as anticancer agents. Attempts have been made to explore the effectivity of drug-delivery systems based on glutamic acid for the delivery of anticancer drugs. Moreover, efforts have also been made to discuss the mechanism of action of glutamic acid derivatives as anticancer agents, clinical applications of glutamic acid derivatives, as well as recent developments and future perspectives of glutamic acid drug development have also been discussed.

  4. Design and synthesis of novel soluble 2,5-diketopiperazine derivatives as potential anticancer agents.

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    Liao, Shengrong; Qin, Xiaochu; Li, Ding; Tu, Zhengchao; Li, Jinsheng; Zhou, Xuefeng; Wang, Junfeng; Yang, Bin; Lin, Xiuping; Liu, Juan; Yang, Xianwen; Liu, Yonghong

    2014-08-18

    Non-protected 2,5-diketopiperazine derivatives have poor solubility thus with negative impact on their bioavailability. In the present study, twenty-one novel soluble mono-protected, and three non-protected 2,5-diketopiperazine derivatives were designed and synthesized. Their anticancer activity to ten cell lines were evaluated by using CCK8 assay, and the results showed that about half of the mono-protected derivatives had broad-spectrum anticancer activity. Among allyl-protected derivatives, compound 4m had strong activity to all the cell lines (IC50 = 0.5-4.5 μM), especially to the cancer cell lines U937 (IC50 = 0.5 μM) and K562 (IC50 = 0.9 μM). Compound 4m could become a lead compound for further development for anticancer agents.

  5. Human-derived normal mesenchymal stem/stromal cells in anticancer therapies

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    Zhang, Cheng; Yang, Shi-Jie; Wen, Qin; Zhong, Jiang F; Chen, Xue-Lian; Stucky, Andres; Press, Michael F; Zhang, Xi

    2017-01-01

    The tumor microenvironment (TME) not only plays a pivotal role during cancer progression and metastasis, but also has profound effects on therapeutic efficacy. Stromal cells of the TME are increasingly becoming a key consideration in the development of active anticancer therapeutics. However, dispute concerning the role of stromal cells to fight cancer continues because the use of mesenchymal stem/stromal cells (MSCs) as an anticancer agent is dependent on the specific MSCs subtype, in vitro or in vivo conditions, factors secreted by MSCs, types of cancer cell lines and interactions between MSCs, cancer cells and host immune cells. In this review, we mainly focus on the role of human-derived normal MSCs in anticancer therapies. We first discuss the use of different MSCs in the therapies for various cancers. We then focus on their anticancer mechanism and clinical application. PMID:28123601

  6. Structure–anticancer activity relationships among 4-azolidinone-3-carboxylic acids derivatives

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    Lesyk R. B.

    2010-04-01

    Full Text Available The aim of present research was investigation of anticancer activity of 4-azolidinone-3-carboxylic acids derivatives, and studies of structure–activity relationships (SAR aspects. Methods. Organic synthesis; spectral methods; anticancer screening was performed according to the US NCI protocol (Developmental Therapeutic Program. Results. The data of new 4-thiazolidinone-3-alkanecarboxylic acids derivatives in vitro anticancer activity were described. The most active compounds which belong to 5-arylidene-2,4- thia(imidazolidinone-3-alkanecarboxylic acids; 5-aryl(heterylidenerhodanine-3-succinic acids derivatives were selected. Determination of some SAR aspects which allowed to determine directions in lead- compounds structure optimization, as well as desirable molecular fragments for design of potential anticancer agents based on 4-azolidinone scaffold were performed. 5-Arylidenehydantoin-3-acetic acids amides were identified as a new class of significant selective antileukemic agents. Possible pharmacophore scaffold of 5-ylidenerhodanine-3-succinic acids derivatives was suggested. Conclusions. The series of active compounds with high anticancer activity and/or selectivity levels were selected. Some SAR aspects were determined and structure design directions were proposed.

  7. Design, synthesis, and anticancer activity of novel berberine derivatives prepared via CuAAC "click" chemistry as potential anticancer agents.

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    Jin, Xin; Yan, Tian-Hua; Yan, Lan; Li, Qian; Wang, Rui-Lian; Hu, Zhen-Lin; Jiang, Yuan-Ying; Sun, Qing-Yan; Cao, Yong-Bing

    2014-01-01

    A series of novel derivatives of phenyl-substituted berberine triazolyls has been designed and synthesized via copper-catalyzed azide-alkyne cycloaddition click chemistry in an attempt to develop antitumor agents. All of the compounds were evaluated for anticancer activity against a panel of three human cancer cell lines, including MCF-7 (breast), SW-1990 (pancreatic), and SMMC-7721 (liver) and the noncancerous human umbilical vein endothelial cell (HUVEC) cell lines. The results indicated that most of the compounds displayed notable anticancer activities against the MCF-7 cells compared with berberine. Among these derivatives, compound 16 showed the most potent inhibitory activity against the SW-1990 and SMMC-7721 cell lines, with half-maximal inhibitory concentration (IC50) values of 8.54±1.97 μM and 11.87±1.83 μM, respectively. Compound 36 exhibited the most potent inhibitory activity against the MCF-7 cell line, with an IC50 value of 12.57±1.96 μM. Compound 16 and compound 36 exhibited low cytotoxicity in the HUVEC cell line, with IC50 values of 25.49±3.24 μM and 30.47±3.47 μM. Furthermore, compounds 14, 15, 16, 17, 18, 32, and 36 exhibited much better selectivity than berberine toward the normal cell line HUVEC.

  8. Synthesis and anticancer activity of some 1,2,3-trisubstituted pyrazinobenzimidazole derivatives.

    Science.gov (United States)

    Demirayak, Şeref; Yurttaş, Leyla

    2014-12-01

    The synthesis of some new pyrazino[1,2-a]benzimidazole derivatives and investigation of their anticancer activities were aimed in this work. Thus, 2-acetylbenzimidazole was reacted with appropriate α-bromoacetophenones and potassium carbonate in acetone to give 2-(2-acetyl-1H-benzimidazol-1-yl)-1-phenylethanone derivatives (3a-d). These diketone compounds were reacted with varied benzylamines in acetic acid to obtain 2-benzyl-1-methylidene-3-aryl-1,2-dihydropyrazino[1,2-a]benzimidazole derivatives (4a-t). The structures of the obtained compounds were elucidated by using IR, (1)H-NMR, (13)C-NMR, MS spectral data and elemental analyses results. Anticancer activities of the selected compounds were investigated in National Cancer Institute, Bethesda, MD. 3c and 4n showed remarkable anticancer activity comparing with standard drugs, melphalan and cisplatin.

  9. Recent developments of C-4 substituted coumarin derivatives as anticancer agents.

    Science.gov (United States)

    Dandriyal, Jyoti; Singla, Ramit; Kumar, Manvendra; Jaitak, Vikas

    2016-08-25

    Cancer is a prominent cause of death in global. Currently, the numbers of drugs that are in clinical practice are having a high prevalence of side effect and multidrug resistance. Researchers have made an attempt to expand a suitable anticancer drug that has no MDR and side effect. Coumarin scaffold became an attractive subject due to their broad spectrum of pharmacological activities. Coumarin derivatives extensively explored for anticancer activities as it possesses minimum side effect along with multi-drug reversal activity. Coumarin derivatives can act by various mechanisms on different tumor cell lines depending on substitution pattern of the core structure of coumarin. Substitution on coumarin nucleus leads to the search for more potent compounds. In this review, we have made an effort to give a synthetic strategy for the preparation of C-4 substituted coumarin derivatives as anticancer agents based on their mechanism of action and also discuss the SAR of the most active compound.

  10. Anticancer activity studies of cubebin isolated from Piper cubeba and its synthetic derivatives.

    Science.gov (United States)

    Rajalekshmi, Dhanya S; Kabeer, Farha A; Madhusoodhanan, Arya R; Bahulayan, Arun K; Prathapan, Remani; Prakasan, Nisha; Varughese, Sunil; Nair, Mangalam S

    2016-04-01

    (-)-Cubebin, isolated from the seeds of Piper cubeba, and its five different types of derivatives (a total of 17), with varying functionalities, were tested for their in vitro anticancer activity against six human cancer cell lines (A549, K562, SiHa, KB, HCT116 and HT29) using MTT assay. Cubebin as well as its derivatives containing lactone and amide groups showed significant anticancer activity. In some of the tested cell lines, the amide derivatives showed higher activity. Morphological analysis indicated that these compounds act through apoptosis mediated pathway of cell death and we expect that these results will pave new paths in the development of novel anticancer agents by the derivatization of (-)-cubebin.

  11. Microwave-assisted one-pot synthesis of polycyclic 4-quinolone derivatives

    OpenAIRE

    2015-01-01

    A microwave-assisted solvent-free one-pot method to afford 1,2,3,4-tetrahydroacridines-9-one derivatives was developed, with shorter reaction time and from easily available starting materials compared to the known methods. Fil: Muscia, Gisela Celeste. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Orgánica; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina; Fil: Carnev...

  12. Synthesis of Quinolone Analogues:7-[(2S, 4R)-2-Aminomethyl-4- hydroxypyrrolidin-1-yl] Quinolones

    Institute of Scientific and Technical Information of China (English)

    Jiu Yu LIU; Hui Yuan GUO

    2004-01-01

    New quinolone derivatives of 7-[(2S, 4R)-2-aminomethyl-4-hydroxypyrrolidin-1-yl] quinolone-3-carboxylic acids were synthesized by condensation of 7-halo substituted quinolone-3-carboxylic acids with (2S, 4R)-2-aminomethyl-4-hydroxypyrrolidine. These compounds were characterized by FAB-MS and 1H NMR.

  13. Synthesis, Antimicrobial and Antitubercular Activities of Some Novel Carboxamide Derivatives of 2-Quinolones

    Directory of Open Access Journals (Sweden)

    Abhishek Kumar

    2014-12-01

    Full Text Available A series of novel substituted N-(3-acetyl-2-oxoquinolin-1(2H-ylbenzamide (AJQC1-AJQC12 have been synthesized upon refluxing 3-acetyl-1-amino-quinolin-2-one and substituted benzoic acid in the presence of dry redistilled pyridine and silicon tetra chloride as coupling agent. 3-acetyl-1-amino-quinolin-2-one (AJQ1-AJQ12 were synthesized from substituted 3-acetyl coumarin upon refluxing with hydrazine hydrate and ethanol. The structures of the final carboxamide derivatives were confirmed by IR, 1H NMR and mass spectra. The synthesized compounds were screened for their antimicrobial activity by tube dilution method and anti tubercular activity by microplate Alamar blue assay. Most of the compounds have exhibited promising antibacterial, anti fungal and anti tubercular activities.

  14. Synthesis, Cytotoxicity and Mechanistic Evaluation of 4-Oxoquinoline-3-carboxamide Derivatives: Finding New Potential Anticancer Drugs

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    Luana da S. M. Forezi

    2014-05-01

    Full Text Available As part of a continuing search for new potential anticancer candidates, we describe the synthesis, cytotoxicity and mechanistic evaluation of a series of 4-oxoquinoline-3-carboxamide derivatives as novel anticancer agents. The inhibitory activity of compounds 10–18 was determined against three cancer cell lines using the MTT colorimetric assay. The screening revealed that derivatives 16b and 17b exhibited significant cytotoxic activity against the gastric cancer cell line but was not active against a normal cell line, in contrast to doxorubicin, a standard chemotherapeutic drug in clinical use. Interestingly, no hemolytical activity was observed when the toxicity of 16b and 17b was tested against blood cells. The in silico and in vitro mechanistic evaluation indicated the potential of 16b as a lead for the development of novel anticancer agents against gastric cancer cells.

  15. ONIOM studies of interaction between single-walled carbon nanotube and gallates derivatives as anticancer agents

    Directory of Open Access Journals (Sweden)

    Nosrat Madadi Mahani

    2017-01-01

    Full Text Available Objective(s: The novel 7-hydroxycoumarinyl gallates derivatives are detected in many pharmaceutical compounds like anticancer and antimicrobial agents. Whereas carbon nanotubes (CNTs have been discussed for nanomedicine applications and in particular as drug delivery systems. The capability of armchair (5, 5 SWCNT -based drug delivery system in the therapy of anticancer has been investigated by quantum mechanics/molecular mechanics method.Materials and Methods: Theoretical investigation of the interaction between armchair (5, 5 SWCNT with gallates derivatives has been fulfilled by quantum mechanics/molecular mechanics (QM/MM method by ONIOM2 (DFT: UFF using the program of GAUSSIAN 03 suite.Results: The results derived from this study, demonstrate  that armchair (5, 5 SWCNT has weak interaction that these interactions contain Vander Waals interactions and indicated clearly that these systems have relatively low durability and so armchair (5, 5 SWCNT is appropriate drug delivery that have been investigated for anti-cancer drug.Conclusion: Analysis of ONIOM2 calculations and the interaction energies of the armchair (5, 5 SWCNT and gallates derivatives represented that this carrier can be utilized to improve the biological and anti-cancer activity of gallates derivatives.

  16. Synthesis, spectral characterization and antimicrobial activity of substituted thiazolyl derivatives of 2-quinolones.

    Science.gov (United States)

    Katagi, M S; Bolakatti, G S; Badiger, A M; Satyanarayana, D; Mamledesai, S N; Sujatha, M L

    2013-02-01

    A series of new 3-(2-substituted amino/substituted hydrazino-1,3-thiazol-4-yl)-4-hydroxy-1-methyl/phenylquinolin-2 (1H)-one hydroiodide 3a-3f and 4a-4f derivatives were prepared by heating 3-Acetyl-4-hydroxy-1-methyl/phenyl quinolin-2 (1H)-one 2a-2b with substituted thiourea and substituted thiosemicarbazide in presence of iodine in n-butanol. The title compounds were characterized on the basis of IR, 1H NMR, 13C NMR and Mass spectral (MS) studies. Further title compounds were evaluated for antibacterial and antifungal by Agar diffusion assay method where as antitubercular activity by Micro-plate Alamar Blue Assay (MABA). Among 12 synthesized novel compounds 3a, 3b, 4d exhibited promising antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa. 3a, 3b, 3e, 4d, 4e showed good antifungal activity against Candida albicans and Aspergillus niger. 3a, 3d, 4d showed good antitubercular activity against Mycobacterium tuberculosis H37Rv strain.

  17. Anti-Cancer Properties of the Naturally Occurring Aphrodisiacs: Icariin and Its Derivatives

    Science.gov (United States)

    Tan, Hui-Li; Chan, Kok-Gan; Pusparajah, Priyia; Saokaew, Surasak; Duangjai, Acharaporn; Lee, Learn-Han; Goh, Bey-Hing

    2016-01-01

    Epimedium (family Berberidaceae), commonly known as Horny Goat Weed or Yin Yang Huo, is commonly used as a tonic, aphrodisiac, anti-rheumatic and anti-cancer agent in traditional herbal formulations in Asian countries such as China, Japan, and Korea. The major bioactive compounds present within this plant include icariin, icaritin and icariside II. Although it is best known for its aphrodisiac properties, scientific and pharmacological studies suggest it possesses broad therapeutic capabilities, especially for enhancing reproductive function and osteoprotective, neuroprotective, cardioprotective, anti-inflammatory and immunoprotective effects. In recent years, there has been great interest in scientific investigation of the purported anti-cancer properties of icariin and its derivatives. Data from in vitro and in vivo studies suggests these compounds demonstrate anti-cancer activity against a wide range of cancer cells which occurs through various mechanisms such as apoptosis, cell cycle modulation, anti-angiogenesis, anti-metastasis and immunomodulation. Of note, they are efficient at targeting cancer stem cells and drug-resistant cancer cells. These are highly desirable properties to be emulated in the development of novel anti-cancer drugs in combatting the emergence of drug resistance and overcoming the limited efficacy of current standard treatment. This review aims to summarize the anti-cancer mechanisms of icariin and its derivatives with reference to the published literature. The currently utilized applications of icariin and its derivatives in cancer treatment are explored with reference to existing patents. Based on the data compiled, icariin and its derivatives are shown to be compounds with tremendous potential for the development of new anti-cancer drugs. PMID:27445824

  18. Anti-Cancer Properties of the Naturally Occurring Aphrodisiacs: Icariin and Its Derivatives.

    Science.gov (United States)

    Tan, Hui-Li; Chan, Kok-Gan; Pusparajah, Priyia; Saokaew, Surasak; Duangjai, Acharaporn; Lee, Learn-Han; Goh, Bey-Hing

    2016-01-01

    Epimedium (family Berberidaceae), commonly known as Horny Goat Weed or Yin Yang Huo, is commonly used as a tonic, aphrodisiac, anti-rheumatic and anti-cancer agent in traditional herbal formulations in Asian countries such as China, Japan, and Korea. The major bioactive compounds present within this plant include icariin, icaritin and icariside II. Although it is best known for its aphrodisiac properties, scientific and pharmacological studies suggest it possesses broad therapeutic capabilities, especially for enhancing reproductive function and osteoprotective, neuroprotective, cardioprotective, anti-inflammatory and immunoprotective effects. In recent years, there has been great interest in scientific investigation of the purported anti-cancer properties of icariin and its derivatives. Data from in vitro and in vivo studies suggests these compounds demonstrate anti-cancer activity against a wide range of cancer cells which occurs through various mechanisms such as apoptosis, cell cycle modulation, anti-angiogenesis, anti-metastasis and immunomodulation. Of note, they are efficient at targeting cancer stem cells and drug-resistant cancer cells. These are highly desirable properties to be emulated in the development of novel anti-cancer drugs in combatting the emergence of drug resistance and overcoming the limited efficacy of current standard treatment. This review aims to summarize the anti-cancer mechanisms of icariin and its derivatives with reference to the published literature. The currently utilized applications of icariin and its derivatives in cancer treatment are explored with reference to existing patents. Based on the data compiled, icariin and its derivatives are shown to be compounds with tremendous potential for the development of new anti-cancer drugs.

  19. Can Some Marine-Derived Fungal Metabolites Become Actual Anticancer Agents?

    Science.gov (United States)

    Gomes, Nelson G M; Lefranc, Florence; Kijjoa, Anake; Kiss, Robert

    2015-06-19

    Marine fungi are known to produce structurally unique secondary metabolites, and more than 1000 marine fungal-derived metabolites have already been reported. Despite the absence of marine fungal-derived metabolites in the current clinical pipeline, dozens of them have been classified as potential chemotherapy candidates because of their anticancer activity. Over the last decade, several comprehensive reviews have covered the potential anticancer activity of marine fungal-derived metabolites. However, these reviews consider the term "cytotoxicity" to be synonymous with "anticancer agent", which is not actually true. Indeed, a cytotoxic compound is by definition a poisonous compound. To become a potential anticancer agent, a cytotoxic compound must at least display (i) selectivity between normal and cancer cells (ii) activity against multidrug-resistant (MDR) cancer cells; and (iii) a preferentially non-apoptotic cell death mechanism, as it is now well known that a high proportion of cancer cells that resist chemotherapy are in fact apoptosis-resistant cancer cells against which pro-apoptotic drugs have more than limited efficacy. The present review thus focuses on the cytotoxic marine fungal-derived metabolites whose ability to kill cancer cells has been reported in the literature. Particular attention is paid to the compounds that kill cancer cells through non-apoptotic cell death mechanisms.

  20. Can Some Marine-Derived Fungal Metabolites Become Actual Anticancer Agents?

    Directory of Open Access Journals (Sweden)

    Nelson G. M. Gomes

    2015-06-01

    Full Text Available Marine fungi are known to produce structurally unique secondary metabolites, and more than 1000 marine fungal-derived metabolites have already been reported. Despite the absence of marine fungal-derived metabolites in the current clinical pipeline, dozens of them have been classified as potential chemotherapy candidates because of their anticancer activity. Over the last decade, several comprehensive reviews have covered the potential anticancer activity of marine fungal-derived metabolites. However, these reviews consider the term “cytotoxicity” to be synonymous with “anticancer agent”, which is not actually true. Indeed, a cytotoxic compound is by definition a poisonous compound. To become a potential anticancer agent, a cytotoxic compound must at least display (i selectivity between normal and cancer cells (ii activity against multidrug-resistant (MDR cancer cells; and (iii a preferentially non-apoptotic cell death mechanism, as it is now well known that a high proportion of cancer cells that resist chemotherapy are in fact apoptosis-resistant cancer cells against which pro-apoptotic drugs have more than limited efficacy. The present review thus focuses on the cytotoxic marine fungal-derived metabolites whose ability to kill cancer cells has been reported in the literature. Particular attention is paid to the compounds that kill cancer cells through non-apoptotic cell death mechanisms.

  1. Plant derived substances with anti-cancer activity: from folklore to practice.

    Science.gov (United States)

    Fridlender, Marcelo; Kapulnik, Yoram; Koltai, Hinanit

    2015-01-01

    Plants have had an essential role in the folklore of ancient cultures. In addition to the use as food and spices, plants have also been utilized as medicines for over 5000 years. It is estimated that 70-95% of the population in developing countries continues to use traditional medicines even today. A new trend, that involved the isolation of plant active compounds begun during the early nineteenth century. This trend led to the discovery of different active compounds that are derived from plants. In the last decades, more and more new materials derived from plants have been authorized and subscribed as medicines, including those with anti-cancer activity. Cancer is among the leading causes of morbidity and mortality worldwide. The number of new cases is expected to rise by about 70% over the next two decades. Thus, there is a real need for new efficient anti-cancer drugs with reduced side effects, and plants are a promising source for such entities. Here we focus on some plant-derived substances exhibiting anti-cancer and chemoprevention activity, their mode of action and bioavailability. These include paclitaxel, curcumin, and cannabinoids. In addition, development and use of their synthetic analogs, and those of strigolactones, are discussed. Also discussed are commercial considerations and future prospects for development of plant derived substances with anti-cancer activity.

  2. Mefloquine-oxazolidine derivatives: a new class of anticancer agents.

    Science.gov (United States)

    Rodrigues, Felipe A R; Bomfim, Igor da S; Cavalcanti, Bruno C; Pessoa, Claudia; Goncalves, Raoni S B; Wardell, James L; Wardell, Solange M S V; de Souza, Marcus V N

    2014-01-01

    A series of 23 racemic mefloquine-oxazolidine derivatives, 4-[3-(aryl)hexahydro[1,3]oxazolo[3,4-a]pyridin-1-yl]-2,8-bis(trifluoromethyl)quinolines, derived from (R*, S*)-(±)-mefloquine and arenealdehydes, have been evaluated for their activity against four cancer cell lines (HCT-8, OVCAR-8, HL-60, and SF-295). Good cytotoxicities have been determined with IC50 values ranging from 0.59 to 4.79 μg/mL. In general compounds with aryl groups having strong electron-releasing substituents, such as HO and MeO, or electron-rich heteroaryl groups, for example imidazol-2-y-l, are active. However, other factors such as steric effects may play a role. As both the active and non-active conformations of the mefloquine-oxazolidine derivatives are similar, it is concluded that molecular conformations do not play a significant role either. This study is the first to evaluate mefloquine derivatives as antitumor agents. The mefloquine-oxazolidine derivatives are considered to be useful leads for the rational design of new antitumor agents.

  3. Anti-cancer efficacy of silybin derivatives -- a structure-activity relationship.

    Directory of Open Access Journals (Sweden)

    Chapla Agarwal

    Full Text Available Silybin or silibinin, a flavonolignan isolated from Milk thistle seeds, is one of the popular dietary supplements and has been extensively studied for its antioxidant, hepatoprotective and anti-cancer properties. We have envisioned that potency of silybin could be further enhanced through suitable modification/s in its chemical structure. Accordingly, here, we synthesized and characterized a series of silybin derivatives namely 2,3-dehydrosilybin (DHS, 7-O-methylsilybin (7OM, 7-O-galloylsilybin (7OG, 7,23-disulphatesilybin (DSS, 7-O-palmitoylsilybin (7OP, and 23-O-palmitoylsilybin (23OP; and compared their anti-cancer efficacy using human bladder cancer HTB9, colon cancer HCT116 and prostate carcinoma PC3 cells. In all the 3 cell lines, DHS, 7OM and 7OG demonstrated better growth inhibitory effects and compared to silybin, while other silybin derivatives showed lesser or no efficacy. Next, we prepared the optical isomers (A and B of silybin, DHS, 7OM and 7OG, and compared their anti-cancer efficacy. Isomers of these three silybin derivatives also showed better efficacy compared with respective silybin isomers, but in each, there was no clear cut silybin A versus B isomer activity preference. Further studies in HTB cells found that DHS, 7OM and 7OG exert better apoptotic activity than silibinin. Clonogenic assays in HTB9 cells further confirmed that both the racemic mixtures as well as pure optical isomers of DHS, 7OM and 7OG were more effective than silybin. Overall, these results clearly suggest that the anti-cancer efficacy of silybin could be significantly enhanced through structural modifications, and identify strong anti-cancer efficacy of silybin derivatives, namely DHS, 7OM, and 7OG, signifying that their efficacy and toxicity should be evaluated in relevant pre-clinical cancer models in rodents.

  4. Design and synthesis of modified quinolones as antitumoral acridones.

    Science.gov (United States)

    Tabarrini, O; Cecchetti, V; Fravolini, A; Nocentini, G; Barzi, A; Sabatini, S; Miao, H; Sissi, C

    1999-06-17

    The bacterial topoisomerase II (DNA gyrase) and the mammalian topoisomerase II represent the cellular targets for quinolone antibacterials and a wide variety of anticancer drugs, respectively. In view of the mechanistic similarities and sequence homologies exhibited by the two enzymes, tentative efforts to selectively shift from an antibacterial to an antitumoral activity was made by synthesizing a series of modified tricyclic quinolones, in which the essential 3-carboxylic function is surrogated by phenolic OH and the classic C-6 fluorine atom is replaced by a NH2 group. The resulting 7-amino-9-acridone derivatives were assayed for their antibacterial as well as cytotoxic activities. No antibacterial activity was found. On the other hand, many derivatives showed significant cytotoxic activity against both HL-60 and P388 leukemias and a wide panel of human and rodent solid tumor cells, derivatives 25 and 26 displaying the best overall antiproliferative activity. Against the LoVo cell line, derivative 25 exhibited higher cytotoxic effects than etoposide.

  5. Synthesis, spectral features and biological activity of some novel hetarylazo dyes derived from 8-chloro-4-hydroxyl-2-quinolone

    Science.gov (United States)

    Yahyazadeh, Asieh; Yousefi, Hessamoddin

    2014-01-01

    In this study, 8-chloro-4-hydroxyl-2-quinolone was synthesized from cyclocondensation of corresponding dianilide and subsequently used as a potent coupling component with some diazotized heterocyclic amines. These compounds were characterized by UV-vis, FT-IR, 1H NMR spectroscopic techniques and elemental analysis. Absorption spectra of these dyes were measured in six polar solvents and discussed with respect to the nature of solvents and substituted groups. The effects of acid, base, temperature and concentration on the visible absorption spectra of the dyes were reported. In addition, the antimicrobial activity of the dyes was explored in detail.

  6. Evolution in medicinal chemistry of ursolic acid derivatives as anticancer agents.

    Science.gov (United States)

    Chen, Haijun; Gao, Yu; Wang, Ailan; Zhou, Xiaobin; Zheng, Yunquan; Zhou, Jia

    2015-03-06

    Currently, there is a renewed interest in common dietaries and plant-based traditional medicines for the prevention and treatment of cancer. In the search for potential anticancer agents from natural sources, ursolic acid (UA), a pentacyclic triterpenoid widely found in various medicinal herbs and fruits, exhibits powerful biological effects including its attractive anticancer activity against various types of cancer cells. However, the limited solubility, rapid metabolism and poor bioavailability of UA restricted its further clinical applications. In the past decade, with substantial progress toward the development of new chemical entities for the treatment of cancer, numerous UA derivatives have been designed and prepared to overcome its disadvantages. Despite extensive effort, discovery of effective UA derivatives has so far met with only limited success. This review summarizes the current status of the structural diversity and evolution in medicinal chemistry of UA analogues and provides a detailed discussion of future direction for further research in the chemical modifications of UA.

  7. Synthesis and Evaluation of Aminothiazole-Paeonol Derivatives as Potential Anticancer Agents

    Directory of Open Access Journals (Sweden)

    Chia-Ying Tsai

    2016-01-01

    Full Text Available In this study, novel aminothiazole-paeonol derivatives were synthesized and characterized using 1H-NMR, 13C-NMR, IR, mass spectroscopy, and high performance liquid chromatography. All the new synthesized compounds were evaluated according to their anticancer effect on seven cancer cell lines. The experimental results indicated that these compounds possess high anticancer potential regarding human gastric adenocarcinoma (AGS cells and human colorectal adenocarcinoma (HT-29 cells. Among these compounds, N-[4-(2-hydroxy-4-methoxyphenylthiazol-2-yl]-4-methoxybenzenesulfonamide (13c had the most potent inhibitory activity, with IC50 values of 4.0 µM to AGS, 4.4 µM to HT-29 cells and 5.8 µM to HeLa cells. The 4-fluoro-N-[4-(2-hydroxy-4-methoxyphenylthiazol-2-yl]benzenesulfonamide (13d was the second potent compound, showing IC50 values of 7.2, 11.2 and 13.8 µM to AGS , HT-29 and HeLa cells, respectively. These compounds are superior to 5-fluorouracil (5-FU for relatively higher potency against AGS and HT-29 human cancer cell lines along with lower cytotoxicity to fibroblasts. Novel aminothiazole-paeonol derivatives in this work might be a series of promising lead compounds to develop anticancer agents for treating gastrointestinal adenocarcinoma.

  8. Hybrid imidazole (benzimidazole)/pyridine (quinoline) derivatives and evaluation of their anticancer and antimycobacterial activity.

    Science.gov (United States)

    Mantu, Dorina; Antoci, Vasilichia; Moldoveanu, Costel; Zbancioc, Gheorghita; Mangalagiu, Ionel I

    2016-01-01

    The design, synthesis, structure, and in vitro anticancer and antimycobacterial activity of new hybrid imidazole (benzimidazole)/pyridine (quinoline) derivatives are described. The strategy adopted for synthesis is straight and efficient, involving a three-step setup procedure: N-acylation, N-alkylation, and quaternization of nitrogen heterocycle. The solubility in microbiological medium and anticancer and antimycobacterial activity of a selection of new synthesized compounds were evaluated. The hybrid derivatives have an excellent solubility in microbiological medium, which make them promising from the pharmacological properties point of view. One of the hybrid compounds, 9 (with a benzimidazole and 8-aminoquinoline skeleton), exhibits a very good and selective antitumor activity against Renal Cancer A498 and Breast Cancer MDA-MB-468. Moreover, the anticancer assay suggests that the hybrid Imz (Bimz)/2-AP (8-AQ) compounds present a specific affinity to Renal Cancer A498. Concerning the antimycobacterial activity, only the hybrid compound, 9, has a significant activity. SAR correlations have been performed.

  9. Adding pharmacogenomics to the development of new marine-derived anticancer agents

    Directory of Open Access Journals (Sweden)

    Aracil Miguel

    2006-01-01

    Full Text Available Abstract Nature has always been a highly productive tool in the development of anticancer therapies. Renewed interest in the potential of this tool has recently been sparked by the realization that the marine ecosystem can be used for the discovery and development of new compounds with clinical potential in advanced resistant tumors. These compounds can be incorporated into combination approaches in a chronic therapy scenario. Our marine anticancer program is using the sea to develop new agents with activity in resistant solid tumors and to identify new cellular targets for therapeutic intervention. This review describes the integration of different pharmacogenomic tools in the development of Yondelis™, Aplidin® and Kahalalide F, three marine-derived compounds currently in Phase II or III development. Our results are reinforcing the targeted selectivity of these agents and opening the gates for customized therapies in cancer patients in the near future.

  10. Synthesis, characterization and anticancer studies of new steroidal oxadiazole, pyrrole and pyrazole derivatives

    Directory of Open Access Journals (Sweden)

    Shamsuzzaman

    2015-07-01

    Full Text Available In the present study steroidal derivatives, 3β-[5′-mercapto-1′,3′,4′-oxadiazole-2-yl]methoxy cholest-5-ene 2, 3β-[2′,5′-dimethylpyrrole-1-yl]aminocarbonylmethoxycholest-5-ene 3 and 3β-[3′,5′-dimethyl pyrazole-1-yl]carbonylmethoxycholest-5-ene 4 have been synthesized from cholest-5-en-3β-O-acetyl hydrazide 1 using CS2/KOH, acetonyl acetone and acetyl acetone, respectively as reagents and are characterized by IR, 1H NMR,13C NMR, MS and elemental analysis. Compounds 2–4 were also evaluated for anticancer activity against human leukemia cell line (HL-60 by MTT assay and compound 4 displayed the promising behavior by showing better anticancer activity.

  11. Metal Complexes of Quinolone Antibiotics and Their Applications: An Update

    Directory of Open Access Journals (Sweden)

    Valentina Uivarosi

    2013-09-01

    Full Text Available Quinolones are synthetic broad-spectrum antibiotics with good oral absorption and excellent bioavailability. Due to the chemical functions found on their nucleus (a carboxylic acid function at the 3-position, and in most cases a basic piperazinyl ring (or another N-heterocycle at the 7-position, and a carbonyl oxygen atom at the 4-position quinolones bind metal ions forming complexes in which they can act as bidentate, as unidentate and as bridging ligand, respectively. In the polymeric complexes in solid state, multiple modes of coordination are simultaneously possible. In strongly acidic conditions, quinolone molecules possessing a basic side nucleus are protonated and appear as cations in the ionic complexes. Interaction with metal ions has some important consequences for the solubility, pharmacokinetics and bioavailability of quinolones, and is also involved in the mechanism of action of these bactericidal agents. Many metal complexes with equal or enhanced antimicrobial activity compared to the parent quinolones were obtained. New strategies in the design of metal complexes of quinolones have led to compounds with anticancer activity. Analytical applications of complexation with metal ions were oriented toward two main directions: determination of quinolones based on complexation with metal ions or, reversely, determination of metal ions based on complexation with quinolones.

  12. Metal complexes of quinolone antibiotics and their applications: an update.

    Science.gov (United States)

    Uivarosi, Valentina

    2013-09-11

    Quinolones are synthetic broad-spectrum antibiotics with good oral absorption and excellent bioavailability. Due to the chemical functions found on their nucleus (a carboxylic acid function at the 3-position, and in most cases a basic piperazinyl ring (or another N-heterocycle) at the 7-position, and a carbonyl oxygen atom at the 4-position) quinolones bind metal ions forming complexes in which they can act as bidentate, as unidentate and as bridging ligand, respectively. In the polymeric complexes in solid state, multiple modes of coordination are simultaneously possible. In strongly acidic conditions, quinolone molecules possessing a basic side nucleus are protonated and appear as cations in the ionic complexes. Interaction with metal ions has some important consequences for the solubility, pharmacokinetics and bioavailability of quinolones, and is also involved in the mechanism of action of these bactericidal agents. Many metal complexes with equal or enhanced antimicrobial activity compared to the parent quinolones were obtained. New strategies in the design of metal complexes of quinolones have led to compounds with anticancer activity. Analytical applications of complexation with metal ions were oriented toward two main directions: determination of quinolones based on complexation with metal ions or, reversely, determination of metal ions based on complexation with quinolones.

  13. Anthracenedione Derivatives as Anticancer Agents Isolated from Secondary Metabolites of the Mangrove Endophytic Fungi

    OpenAIRE

    Jian-ye Zhang; Li-yang Tao; Yong-ju Liang; Li-ming Chen; Yan-jun Mi; Li-sheng Zheng; Fang Wang; Zhi-gang She; Yong-cheng Lin; Kenneth Kin Wah To; Li-wu Fu

    2010-01-01

    In this article, we report anticancer activity of 14 anthracenedione derivatives separated from the secondary metabolites of the mangrove endophytic fungi Halorosellinia sp. (No. 1403) and Guignardia sp. (No. 4382). Some of them inhibited potently the growth of KB and KBv200 cells, among which compound 6 displayed strong cytotoxicity with IC50 values of 3.17 and 3.21 μM to KB and KBv200 cells, respectively. Furthermore, we demonstrate that the mechanism involved in the apoptosis induced by co...

  14. Anthracenedione derivatives as anticancer agents isolated from secondary metabolites of the mangrove endophytic fungi.

    Science.gov (United States)

    Zhang, Jian-ye; Tao, Li-yang; Liang, Yong-ju; Chen, Li-ming; Mi, Yan-jun; Zheng, Li-sheng; Wang, Fang; She, Zhi-gang; Lin, Yong-cheng; To, Kenneth Kin Wah; Fu, Li-wu

    2010-04-23

    In this article, we report anticancer activity of 14 anthracenedione derivatives separated from the secondary metabolites of the mangrove endophytic fungi Halorosellinia sp. (No. 1403) and Guignardia sp. (No. 4382). Some of them inhibited potently the growth of KB and KBv200 cells, among which compound 6 displayed strong cytotoxicity with IC(50) values of 3.17 and 3.21 microM to KB and KBv200 cells, respectively. Furthermore, we demonstrate that the mechanism involved in the apoptosis induced by compound 6 is probably related to mitochondrial dysfunction. Additionally, the structure-activity relationships of these compounds are discussed.

  15. Anthracenedione Derivatives as Anticancer Agents Isolated from Secondary Metabolites of the Mangrove Endophytic Fungi

    Directory of Open Access Journals (Sweden)

    Jian-ye Zhang

    2010-04-01

    Full Text Available In this article, we report anticancer activity of 14 anthracenedione derivatives separated from the secondary metabolites of the mangrove endophytic fungi Halorosellinia sp. (No. 1403 and Guignardia sp. (No. 4382. Some of them inhibited potently the growth of KB and KBv200 cells, among which compound 6 displayed strong cytotoxicity with IC50 values of 3.17 and 3.21 μM to KB and KBv200 cells, respectively. Furthermore, we demonstrate that the mechanism involved in the apoptosis induced by compound 6 is probably related to mitochondrial dysfunction. Additionally, the structure-activity relationships of these compounds are discussed.

  16. Evaluation on the inhibition of pyrrol-2-yl ethanone derivatives to lactate dehydrogenase and anticancer activities

    Science.gov (United States)

    Lu, Na-Na; Weng, Zhao-Yue; Chen, Qiu-Yun; Boison, Daniel; Xiao, Xin-Xin; Gao, Jing

    2016-08-01

    Lactate dehydrogenase A (LDH-A) is a potentially important metabolic target for the inhibition of the highly activated glycolysis pathway in cancer cells. In order to develop bifunctional compounds as inhibitor of LDH-A and anticancer agents, two pyrrol-2-yl methanone (or ethanone) derivatives (PM1 and PM2) were synthesized and evaluated as inhibitors of LDH-A based on the enzyme assay and cell assay by spectroscopy analysis. Fluorescence and CD spectra results demonstrated that both the change of second structure of LDH-A and the affinity interaction for compounds to LDH-A gave great effect on the activity of LDH-A. In particular, low concentration of compounds (1 μμ-25 μμ) could change the level of pyruvate in cancer cells. Moreover, the in vitro assay results demonstrated that pyrrol-2-yl ethanone derivatives can inhibit the proliferation of cancer cells. Therefore, pyrrol-2-yl ethanone derivatives (PM2) can be both LDH-A inhibitor and anticancer agents.

  17. Dysglycemia associated with quinolones.

    Science.gov (United States)

    El Ghandour, Sarah; Azar, Sami T

    2015-06-01

    Antimicrobial therapy is well known to be associated with fluctuations of blood glucose levels. This review aims at exploring the association between glycemic fluctuations and antibiotics mainly focusing on quinolones. Quinolones are associated with hypoglycemia and hyperglycemia. Several mechanism are proposed to explain this causality.

  18. Synthesis, crystal structure, superoxide scavenging activity, anticancer and docking studies of novel adamantyl nitroxide derivatives

    Science.gov (United States)

    Zhu, Xiao-he; Sun, Jin; Wang, Shan; Bu, Wei; Yao, Min-na; Gao, Kai; Song, Ying; Zhao, Jin-yi; Lu, Cheng-tao; Zhang, En-hu; Yang, Zhi-fu; Wen, Ai-dong

    2016-03-01

    A novel adamantyl nitroxide derivatives has been synthesized and characterized by IR, ESI-MS and elemental analysis. Quantum chemical calculations have also been performed to calculate the molecular geometry using density functional theory (B3LYP) with the 6-31G (d,p) basis set. The calculated results showed that the optimized geometry can well reproduce the crystal structure. The antioxidant and antiproliferative activity were evaluated by superoxide (NBT) and MTT assay. The adamantyl nitroxide derivatives exhibited stronger scavenging ability towards O2· - radicals when compared to Vitamin C, and demonstrated a remarked anticancer activity against all the tested cell lines, especially Bel-7404 cells with IC50 of 43.3 μM, compared to the positive control Sorafenib (IC50 = 92.0 μM). The results of molecular docking within EGFR using AutoDock confirmed that the titled compound favorably fitted into the ATP binding site of EGFR and would be a potential anticancer agent.

  19. Synthesis, characterization and in vitro anticancer evaluations of two novel derivatives of deferasirox iron chelator.

    Science.gov (United States)

    Salehi, Samie; Saljooghi, Amir Sh; Shiri, Ali

    2016-06-15

    Iron (Fe) chelation therapy was initially designed to alleviate the toxic effects of excess Fe evident in Fe-overload diseases. However, the novel toxicological properties of some Fe chelator-metal complexes have shifted significant attention to their application in cancer chemotherapy. The present study investigates the new role of deferasirox as an anticancer agent due to its ability to chelate with iron. Because of aminoacids antioxidant effect, deferasirox and its two novel amino acid derivatives have been synthesized through the treatment of deferasirox with DCC as well as glycine or phenylalanine methyl ester. All new compounds have been characterized by elemental analysis, FT-IR NMR and mass spectrometry. Therefore, the cytotoxicity of these compounds was screened for antitumor activity against some cell lines using cisplatin as a comparative standard by MTT assay and Flow cytometry. The impact of iron in the intracellular generation of reactive oxygen species was assessed on HT29 and MDA-MB-231 cells. The potential of the synthesized iron chelators for their efficacy to protect cells against model oxidative injury induced was compared. The reactive oxygen species intracellular fluorescence intensity were measured and the result showed that the reactive oxygen species intensity after iron incubation increased while after chelators incubation the reactive oxygen species intensity were decreased significantly. Besides, the effect of the synthesized compounds on mouse fibroblast cell line (L929) was simultaneously evaluated as control. The pharmacological results showed that deferasirox and its two novel aminoacid derivatives were potent anticancer agents.

  20. A QSAR study and molecular design of benzothiazole derivatives as potent anticancer agents

    Institute of Scientific and Technical Information of China (English)

    CHEN JinCan; QIAN Li; SHEN Yong; CHEN LanMei; ZHENG KangCheng

    2008-01-01

    A quantitative structure-activity relationship (QSAR) of a series of benzothiazole derivatives showing a potent and selective cytotoxicity against a tumorigenic cell line has been studied by using the density functional theory (DFT), molecular mechanics (MM+) and statistical methods, and the QSAR equation was established via a correlation analysis and a stepwise regression analysis.A new scheme deter-mining outliers by "leave-one-out" (LOO) cross-validation coefficient (q2n-1) was suggested and suc-cessfully used.In the established optimal equation (excluding two outliers), the steric parameter (MRR) and the net charge (QFR) of the first atom of the substituent (R), as well as the square of hydrophobic parameter (IgP)2 of the whole molecule, are the main independent factors contributing to the anticancer activities of the compounds.The fitting correlation coefficient (R2) and the cross-validation coefficient (q2) values are 0.883 and 0.797, respectively.It indicates that this model has a significantly statistical quality and an excellent prediction ability.Based on the QSAR studies, 4 new compounds with high predicted anticancer activities have been theoretically designed and they are expected to be confirmed experimentally.

  1. A QSAR study and molecular design of benzothiazole derivatives as potent anticancer agents

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A quantitative structure-activity relationship (QSAR) of a series of benzothiazole derivatives showing a potent and selective cytotoxicity against a tumorigenic cell line has been studied by using the density functional theory (DFT), molecular mechanics (MM+) and statistical methods, and the QSAR equation was established via a correlation analysis and a stepwise regression analysis. A new scheme determining outliers by "leave-one-out" (LOO) cross-validation coefficient (q2n-i) was suggested and successfully used. In the established optimal equation (excluding two outliers), the steric parameter (MRR) and the net charge (QFR) of the first atom of the substituent (R), as well as the square of hydrophobic parameter (lgP)2 of the whole molecule, are the main independent factors contributing to the anticancer activities of the compounds. The fitting correlation coefficient (R2) and the cross-validation coefficient (q2) values are 0.883 and 0.797, respectively. It indicates that this model has a significantly statistical quality and an excellent prediction ability. Based on the QSAR studies, 4 new compounds with high predicted anticancer activities have been theoretically designed and they are expected to be confirmed experimentally.

  2. A phenotypic screening approach to identify anticancer compounds derived from marine fungi.

    Science.gov (United States)

    Ellinger, Bernhard; Silber, Johanna; Prashar, Anjali; Landskron, Johannes; Weber, Jonas; Rehermann, Sarah; Müller, Franz-Josef; Smith, Stephen; Wrigley, Stephen; Taskén, Kjetil; Gribbon, Philip; Labes, Antje; Imhoff, Johannes F

    2014-04-01

    This study covers the isolation, testing, and identification of natural products with anticancer properties. Secondary metabolites were isolated from fungal strains originating from a variety of marine habitats. Strain culture protocols were optimized with respect to growth media composition and fermentation conditions. From these producers, isolated compounds were screened for their effect on the viability and proliferation of a subset of the NCI60 panel of cancer cell lines. Active compounds of interest were identified and selected for detailed assessments and structural elucidation using nuclear magnetic resonance. This revealed the majority of fungal-derived compounds represented known anticancer chemotypes, confirming the integrity of the process and the ability to identify suitable compounds. Examination of effects of selected compounds on cancer-associated cell signaling pathways used phospho flow cytometry in combination with 3D fluorescent cell barcoding. In parallel, the study addressed the logistical aspects of maintaining multiple cancer cell lines in culture simultaneously. A potential solution involving microbead-based cell culture was investigated (BioLevitator, Hamilton). Selected cell lines were cultured in microbead and 2D methods and cell viability tests showed comparable compound inhibition in both methods (R2=0.95). In a further technology assessment, an image-based assay system was investigated for its utility as a possible complement to ATP-based detection for quantifying cell growth and viability in a label-free manner.

  3. Synthesis of dihydropyrazole sulphonamide derivatives that act as anti-cancer agents through COX-2 inhibition.

    Science.gov (United States)

    Qiu, Han-Yue; Wang, Peng-Fei; Li, Zhen; Ma, Jun-Ting; Wang, Xiao-Ming; Yang, Yong-Hua; Zhu, Hai-Liang

    2016-02-01

    COX-2 has long been exploited in the treatment of inflammation and relief of pain; however, research increasingly suggests COX-2 inhibitors might possess potential benefits to thwart tumour processes. In the present study, we designed a series of novel COX-2 inhibitors based on analysis of known inhibitors combined with an in silico scaffold modification strategy. A docking simulation combined with a primary screen in vitro were performed to filter for the lead compound, which was then substituted, synthesized and evaluated by a variety of bioassays. Derivative 4d was identified as a potent COX-2 enzyme inhibitor and exerted an anticancer effect through COX-2 inhibition. Further investigation confirmed that 4d could induce A549 cell apoptosis and arrest the cell cycle at the G2/M phase. Moreover, treatment with 4d reduced A549 cell adhesive ability and COX-2 expression. The morphological variation of treated cells was also visualized by confocal microscopy. Overall, the biological profile of 4d suggests that this compound may be developed as a potential anticancer agent.

  4. Synthesis and anticancer evaluation of 2-phenyl thiaolidinone substituted 2-phenyl benzothiazole-6-carboxylic acid derivatives

    Directory of Open Access Journals (Sweden)

    Padmavathi P. Prabhu

    2015-03-01

    Full Text Available A novel series of 2-(3-(4-oxo-2-substituted phenyl thiazolidin-3-ylphenylbenzo[d]thiazole-6-carboxylic acid derivatives PP1–PP8 were synthesized by various benzothiazole Schiff’s bases by reaction with thioglycollic acid. Their structures were established on the basis of IR, 1H-NMR, 13C-NMR, mass spectral data and elemental analysis. All the synthesized compounds were screened for their in vitro anticancer activity by 3-(4,5-dimethyl thiazole-2yl-2,5-diphenyltetrazoliumbromide (MTT assay on human cervical cancer cell line (HeLa cell lines. Among these compound PP2 exhibited most significant activity as compared with PP5, PP7 and PP8. However, the activity was less as compared to the standard drug Cisplatin.

  5. Synthesis and Biological Evaluation of Novel Benzothiazole-2-thiol Derivatives as Potential Anticancer Agents

    Directory of Open Access Journals (Sweden)

    Luo-Ting Yu

    2012-03-01

    Full Text Available A series of novel benzothiazole-2-thiol derivatives were synthesized and their structures determined by 1H-NMR, 13C-NMR and HRMS (ESI. The effects of all compounds on a panel of different types of human cancer cell lines were investigated. Among them, pyridinyl-2-amine linked benzothiazole-2-thiol compounds 7d, 7e, 7f and 7i exhibited potent and broad-spectrum inhibitory activities. Compound 7e displayed the most potent anticancer activity on SKRB-3 (IC50 = 1.2 nM, SW620 (IC50 = 4.3 nM, A549 (IC50 = 44 nM and HepG2 (IC50 = 48 nM and was found to induce apoptosis in HepG2 cancer cells.

  6. Synthesis, characterization and evaluation of antioxidant and anticancer activities of novel benzisoxazole-substituted-allyl derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Anand, Mohanam [Kingston Engineering College, Vellore (India); Selvaraj, Vaithialingam [University College of Engineering-Villupuram, Villupuram (India); Alagar, Muthukaruppan [Anna University, Chennai (India)

    2014-04-15

    A novel series of various 2-allylbenzo[d]isoxazol-3(2H)-ones were synthesized using benzo[d]isoxazol-3(2H)-one treated with different allyl bromides/chlorides in the presence of water-mediated cesium carbonate as a new catalyst 3(a-h). The structures of the newly synthesized Benzisoxazole-substituted-allyl derivatives were characterized by spectroscopic methods and mass spectrometry. These synthesized compounds were evaluated for their in vitro antioxidant and anticancer activity. Compounds 3b, d, f, h were identified as the best hit against HT-29 Human colon cancer cells. Similarly, compounds like 3b, d, f, h showed significant antioxidant activity compared to the standard drug butylated hydroxy toluene (BHT)

  7. Synthesis and in vitro antitumor activity of substituted quinazoline and quinoxaline derivatives: search for anticancer agent.

    Science.gov (United States)

    Noolvi, Malleshappa N; Patel, Harun M; Bhardwaj, Varun; Chauhan, Ankit

    2011-06-01

    The synthesis of some 2-furano-4(3H)-quinazolinones, diamides (open ring quinazolines), quinoxalines and their biological evaluation as antitumor agents using National Cancer Institute (NCI) disease oriented antitumor screen protocol are investigated. Among the synthesize compounds, seventeen compounds were granted NSC code and screened at National Cancer Institute (NCI), USA for anticancer activity at a single high dose (10(-5) M) in full NCI 60 cell panel. Among the selected compounds, 3-(2-chloro benzylideneamine)-2-(furan-2-yl) quinazoline-4(3h)-one 21 was found to be the most active candidate of the series at five dose level screening against Ovarian OVCAR-4 and Non-small cell lung cancer NCI-H522 with GI50 1.82 & 2.14 μM respectively. Rational approach and QSAR techniques enabled the understanding of the pharmacophoric requirement for quinazoline, diamides and quinoxaline derivatives.

  8. Rational design of biaryl pharmacophore inserted noscapine derivatives as potent tubulin binding anticancer agents

    Science.gov (United States)

    Santoshi, Seneha; Manchukonda, Naresh Kumar; Suri, Charu; Sharma, Manya; Sridhar, Balasubramanian; Joseph, Silja; Lopus, Manu; Kantevari, Srinivas; Baitharu, Iswar; Naik, Pradeep Kumar

    2015-03-01

    We have strategically designed a series of noscapine derivatives by inserting biaryl pharmacophore (a major structural constituent of many of the microtubule-targeting natural anticancer compounds) onto the scaffold structure of noscapine. Molecular interaction of these derivatives with α,β-tubulin heterodimer was investigated by molecular docking, molecular dynamics simulation, and binding free energy calculation. The predictive binding affinity indicates that the newly designed noscapinoids bind to tubulin with a greater affinity. The predictive binding free energy (ΔGbind, pred) of these derivatives (ranging from -5.568 to -5.970 kcal/mol) based on linear interaction energy (LIE) method with a surface generalized Born (SGB) continuum solvation model showed improved binding affinity with tubulin compared to the lead compound, natural α-noscapine (-5.505 kcal/mol). Guided by the computational findings, these new biaryl type α-noscapine congeners were synthesized from 9-bromo-α-noscapine using optimized Suzuki reaction conditions for further experimental evaluation. The derivatives showed improved inhibition of the proliferation of human breast cancer cells (MCF-7), human cervical cancer cells (HeLa) and human lung adenocarcinoma cells (A549), compared to natural noscapine. The cell cycle analysis in MCF-7 further revealed that these compounds alter the cell cycle profile and cause mitotic arrest at G2/M phase more strongly than noscapine. Tubulin binding assay revealed higher binding affinity to tubulin, as suggested by dissociation constant (Kd) of 126 ± 5.0 µM for 5a, 107 ± 5.0 µM for 5c, 70 ± 4.0 µM for 5d, and 68 ± 6.0 µM for 5e compared to noscapine (Kd of 152 ± 1.0 µM). In fact, the experimentally determined value of ΔGbind, expt (calculated from the Kd value) are consistent with the predicted value of ΔGbind, pred calculated based on LIE-SGB. Based on these results, one of the derivative 5e of this series was used for further toxicological

  9. Synthesis of novel polybrominated benzimidazole derivatives-potential CK2 inhibitors with anticancer and proapoptotic activity.

    Science.gov (United States)

    Łukowska-Chojnacka, Edyta; Wińska, Patrycja; Wielechowska, Monika; Poprzeczko, Martyna; Bretner, Maria

    2016-02-15

    The efficient method for the synthesis of novel cell permeable inhibitors of protein kinase CK2 with anticancer and proapoptotic activity has been developed. A series of polybrominated benzimiadazole derivatives substituted by various cyanoalkyl groups have been synthesized. Cyanoethyl derivatives were obtained by Michael type addition of 4,5,6,7-tetrabromo-1H-benzimidazole (TBBi) and 4,5,6,7-tetrabromo-2-methyl-1H-benzimidazole to acrylonitrile, whilst cyanomethyl, cyanopropyl and cyanobutyl analogs by N-alkylation of 4,5,6,7-tetrabromo-1H-benzimidazole and 4,5,6,7-tetrabromo-2-methyl-1H-benzimidazole with appropriate cyanoalkyl halides. The inhibitory activity against protein kinase rhCK2α catalytic subunit and cytotoxicity against two human cancer cell lines: acute lymphocytic leukemia (CCRF-CEM) and breast (MCF-7) were evaluated for all newly synthesized compounds. Additionally, the proapoptotic activity toward leukemia cells and intracellular inhibition of CK2 for the most cytotoxic derivatives have been performed, demonstrating 4,5,6,7-tetrabromo-2-methyl-1H-benzimidazole as a new selective inhibitor of rhCK2 with twenty-fold better proapoptotic activity than parental compound (TBBi).

  10. N-Phenyl-2-p-tolylthiazole-4-carboxamide derivatives: Syn-thesis and cytotoxicity evaluation as anticancer agents

    Directory of Open Access Journals (Sweden)

    Ahmad Mohammadi-Farani

    2014-07-01

    Conclusion: A new series of phenylthiazole derivatives were synthesized and their anticancer activity was assessed against cancerous cell lines. More structural modifications and derivatization is necessary to achieve to the more potent compounds.       

  11. Synthesis of some pyrazolines and pyrimidines derived from polymethoxy chalcones as anticancer and antimicrobial agents.

    Science.gov (United States)

    Rostom, Sherif A F; Badr, Mona H; Abd El Razik, Heba A; Ashour, Hayam M A; Abdel Wahab, Abeer E

    2011-09-01

    The synthesis of a series of certain polymethoxy chalcones and some derived pyrazole, pyrimidine, and thiazolopyrimidine ring structures is reported. Eleven compounds 4, 6, 9, 11, 14-17, 22, 24, and 25 were selected by the National Cancer Institute (NCI) to be screened for their in-vitro anticancer activity, whereas all the synthesized compounds were evaluated for their in-vitro antimicrobial activity. Compounds 4, 6, and 11 were found to possess a significant broad spectrum antitumor potential against most of the tested subpanel tumor cell lines. The pyrazolines 4 and 6 displayed remarkable growth inhibitory activities (GI(50) MG-MID values of 2.10 and 1.38 µM, respectively), together with moderate cytostatic effects (TGI MG-MID values of 47.9 and 42.7 µM, respectively). Meanwhile, the pyrimidin-2-one 11 showed a noticeable overall tumor growth inhibitory activity, together with high cytostatic and cytotoxic efficacies (GI(50) , TGI and LC(50) MG-MID values of 3.39, 17.4, and 61.7 µM, respectively). On the other hand, compounds 3, 4, 13, 15, 19, 20, and 23 were found to be the most active antimicrobial members in this investigation with a broad spectrum of activity. Compound 23 was four times superior to ampicillin against Pseudomonas aeruginosa. The best antifungal activity was demonstrated by compounds 4, 5, and 11 which possessed almost half the activity of clotrimazole against Candida albicans. Collectively, the obtained biological results suggest that compound 4 could be considered as a possible dual antimicrobial-anticancer agent.

  12. Isatin Derived Spirocyclic Analogues with α-Methylene-γ-butyrolactone as Anticancer Agents: A Structure-Activity Relationship Study.

    Science.gov (United States)

    Rana, Sandeep; Blowers, Elizabeth C; Tebbe, Calvin; Contreras, Jacob I; Radhakrishnan, Prakash; Kizhake, Smitha; Zhou, Tian; Rajule, Rajkumar N; Arnst, Jamie L; Munkarah, Adnan R; Rattan, Ramandeep; Natarajan, Amarnath

    2016-05-26

    Design, synthesis, and evaluation of α-methylene-γ-butyrolactone analogues and their evaluation as anticancer agents is described. SAR identified a spirocyclic analogue 19 that inhibited TNFα-induced NF-κB activity, cancer cell growth and tumor growth in an ovarian cancer model. A second iteration of synthesis and screening identified 29 which inhibited cancer cell growth with low-μM potency. Our data suggest that an isatin-derived spirocyclic α-methylene-γ-butyrolactone is a suitable core for optimization to identify novel anticancer agents.

  13. Anti-cancer activity of novel dibenzo[b,f]azepine tethered isoxazoline derivatives

    Directory of Open Access Journals (Sweden)

    Sadashiva Maralinganadoddi

    2012-10-01

    Full Text Available Background Dibenzoazepine (DB derivatives are important and valuable compounds in medicinal chemistry. The synthesis and chemotherapeutic properties of naturally occurring DBs and different heterocyclic moiety tethered DBs are reported. Herein, we report the DB-fused hybrid structure that containing isoxazolines (DBIs and their anti-cancer activity, which could throw light on the structural and functional features of new molecules. Results and Conclusion The synthesis and characterization of novel ring DB tethered isoxazoline derivatives (DBIs were carried out. After the detailed structural characterization using 2D-NMR experiments, the compounds were identified as 5-substituted isoxazolines. The effect of newly synthesized DBIs against the invasion of murine osteosarcoma (LM8G7 cells was studied. Among the tested molecules, compound 4g (5-[−3-(4-chlorophenyl-4,5-dihydroisoxazol-5-yl-methyl]-5 H-dibenzo[b,f]azepine, was found to inhibit the invasion of LM8G7 cells strongly, when compared to other structurally related compounds. Cumulatively, the compound 4g inhibited the invasion MDA-MB-231 cells completely at 10 μM. In addition to anti-invasion property the compound 4g also inhibited the migration of LM8G7 and human ovarian cancer cells (OVSAHO dose-dependently. Compound 4g inhibited the proliferation of LM8G7, OVSAHO, human breast cancer cells (MCF-7 and human melphalan-resistant multiple myeloma (RPMI8226-LR5 cells that are comparable to cisplatin and suramin.

  14. Progress Toward the Development of Noscapine and Derivatives as Anticancer Agents.

    Science.gov (United States)

    DeBono, Aaron; Capuano, Ben; Scammells, Peter J

    2015-08-13

    Many nitrogen-moiety containing alkaloids derived from plant origins are bioactive and play a significant role in human health and emerging medicine. Noscapine, a phthalideisoquinoline alkaloid derived from Papaver somniferum, has been used as a cough suppressant since the mid 1950s, illustrating a good safety profile. Noscapine has since been discovered to arrest cells at mitosis, albeit with moderately weak activity. Immunofluorescence staining of microtubules after 24 h of noscapine exposure at 20 μM elucidated chromosomal abnormalities and the inability of chromosomes to complete congression to the equatorial plane for proper mitotic separation ( Proc. Natl. Acad. Sci. U. S. A. 1998 , 95 , 1601 - 1606 ). A number of noscapine analogues possessing various modifications have been described within the literature and have shown significantly improved antiprolific profiles for a large variety of cancer cell lines. Several semisynthetic antimitotic alkaloids are emerging as possible candidates as novel anticancer therapies. This perspective discusses the advancing understanding of noscapine and related analogues in the fight against malignant disease.

  15. Synthesis of 4-hydroxy-2(1H)-quinolone derived chalcones, pyrazolines and their antimicrobial, in silico antimalarial evaluations.

    Science.gov (United States)

    Sarveswari, S; Vijayakumar, V; Siva, R; Priya, R

    2015-01-01

    A few derivatives of 3-(4,5-dihydro-5-aryl-1-phenyl-1H-pyrazol-3-yl)-4-hydroxyquinolin-2(1H)-ones (5a-j) that are synthesized from 4-hydroxy-3-(3-arylacryloyl)quinolin-2(1H)-ones (4a-j) by microwave-assisted synthesis are screened for their antimicrobial, in silico antimalarial activities. Among the tested compounds 4h and 5d were found to have a potent antimalarial activity than the standards, and the others are found to show considerable antimalarial activity and moderate antimicrobial activity.

  16. Plant-derived anticancer agents: a promising treatment for bone metastasis

    Science.gov (United States)

    Juárez, Patricia

    2014-01-01

    Bone metastasis is a very frequent complication of advanced cancer, and it remains an incurable disease. Current therapies that have been approved for the treatment of bone metastases delay the occurrence of skeletal-related events and can extend the patient's lifespan by a few years. However, they will not cure or cause the regression of established bone metastases, and new side effects are emerging after prolonged treatment. Thus, new therapies are severely needed. There are compelling evidences from in vitro and in vivo preclinical studies that support the use of compounds derived from plants to treat several forms of cancers including bone metastasis. More than 25% of the drugs used during the past 20 years were directly derived from plants, whereas another 25% are chemically altered natural products. Still, only 5–15% of the ∼250 000 higher plants have ever been investigated for bioactive compounds. There is a growing interest for the study of anticancer drugs with relatively low side effects that target specific key signaling pathways that control the establishment and progression of the cancer metastasis. Therefore, further studies are needed to identify new natural compounds with high efficiency in cancer prevention and treatment. Extensive reviews about plant-derived agents and their use in cancer have been published, but none when it comes to the treatment of bone metastases. Only a few of these compounds have been evaluated for the treatment of bone metastasis; here we describe some of the most prominent ones that are having the potential to reach the clinic soon.

  17. Synthesis, Characterization and Anti-Cancer Activity of Hydrazide Derivatives Incorporating a Quinoline Moiety

    Directory of Open Access Journals (Sweden)

    Murat Bingul

    2016-07-01

    Full Text Available Identification of the novel (E-N′-((2-chloro-7-methoxyquinolin-3-ylmethylene-3-(phenylthiopropanehydrazide scaffold 18 has led to the development of a new series of biologically active hydrazide compounds. The parent compound 18 and new quinoline derivatives 19–26 were prepared from the corresponding quinoline hydrazones and substituted carboxylic acids using EDC-mediated peptide coupling reactions. Further modification of the parent compound 18 was achieved by replacement of the quinoline moiety with other aromatic systems. All the newly synthesized compounds were evaluated for their anti-cancer activity against the SH-SY5Y and Kelly neuroblastoma cell lines, as well as the MDA-MB-231 and MCF-7 breast adenocarcinoma cell lines. Analogues 19 and 22 significantly reduced the cell viability of neuroblastoma cancer cells with micromolar potency and significant selectivity over normal cells. The quinoline hydrazide 22 also induced G1 cell cycle arrest, as well as upregulation of the p27kip1 cell cycle regulating protein.

  18. Apigenin as an anti-quinolone-resistance antibiotic.

    Science.gov (United States)

    Morimoto, Yuh; Baba, Tadashi; Sasaki, Takashi; Hiramatsu, Keiichi

    2015-12-01

    We previously reported the first 'reverse antibiotic' (RA), nybomycin (NYB), which showed a unique antimicrobial activity against Staphylococcus aureus strains. NYB specifically suppressed the growth of quinolone-resistant S. aureus strains but was not effective against quinolone-susceptible strains. Although NYB was first reported in 1955, little was known about its unique antimicrobial activity because it was before the synthesis of the first quinolone ('old quinolone'), nalidixic acid, in 1962. Following our re-discovery of NYB, we looked for other RAs among natural substances that act on quinolone-resistant bacteria. Commercially available flavones were screened against S. aureus, including quinolone-resistant strains, and their minimum inhibitory concentrations (MICs) were compared using the microbroth dilution method. Some of the flavones screened showed stronger antimicrobial activity against quinolone-resistant strains than against quinolone-susceptible ones. Amongst them, apigenin (API) was the most potent in its RA activity. DNA cleavage assay showed that API inhibited DNA gyrase harbouring the quinolone resistance mutation gyrA(Ser84Leu) but did not inhibit 'wild-type' DNA gyrase that is sensitive to levofloxacin. An API-susceptible S. aureus strain Mu50 was also selected using agar plates containing 20mg/L API. Whole-genome sequencing of selected mutant strains was performed and frequent back-mutations (reverse mutations) were found among API-resistant strains derived from the API-susceptible S. aureus strains. Here we report that API represents another molecular class of natural antibiotic having RA activity against quinolone-resistant bacteria.

  19. Design, synthesis, and anticancer activity of novel berberine derivatives prepared via CuAAC “click” chemistry as potential anticancer agents

    Directory of Open Access Journals (Sweden)

    Jin X

    2014-08-01

    Full Text Available Xin Jin1,2,* Tian-Hua Yan,3,* Lan Yan,1 Qian Li,4 Rui-Lian Wang,1 Zhen-Lin Hu,1 Yuan-Ying Jiang,1 Qing-Yan Sun,1 Yong-Bing Cao1 1School of Pharmacy, Second Military Medical University, Shanghai, People's Republic of China; 2School of Pharmacy, FuJian University of Traditional Chinese Medicine, Fuzhou, People's Republic of China; 3Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing, People's Republic of China; 4Diakite Biological Technology Co., Ltd, Shanghai, People's Republic of China *These authors contributed equally to this work Abstract: A series of novel derivatives of phenyl-substituted berberine triazolyls has been designed and synthesized via copper-catalyzed azide-alkyne cycloaddition click chemistry in an attempt to develop antitumor agents. All of the compounds were evaluated for anticancer activity against a panel of three human cancer cell lines, including MCF-7 (breast, SW-1990 (pancreatic, and SMMC-7721 (liver and the noncancerous human umbilical vein endothelial cell (HUVEC cell lines. The results indicated that most of the compounds displayed notable anticancer activities against the MCF-7 cells compared with berberine. Among these derivatives, compound 16 showed the most potent inhibitory activity against the SW-1990 and SMMC-7721 cell lines, with half-maximal inhibitory concentration (IC50 values of 8.54±1.97 µM and 11.87±1.83 µM, respectively. Compound 36 exhibited the most potent inhibitory activity against the MCF-7 cell line, with an IC50 value of 12.57±1.96 µM. Compound 16 and compound 36 exhibited low cytotoxicity in the HUVEC cell line, with IC50 values of 25.49±3.24 µM and 30.47±3.47 µM. Furthermore, compounds 14, 15, 16, 17, 18, 32, and 36 exhibited much better selectivity than berberine toward the normal cell line HUVEC. Keywords: berberine, anticancer, click chemistry, structure–activity relationship

  20. Evolution in Medicinal Chemistry of Ursolic Acid Derivatives as Anticancer Agents

    OpenAIRE

    Chen, Haijun; Gao, Yu; Wang, Ailan; Zhou, Xiaobin; Zheng, Yunquan; Zhou, Jia

    2015-01-01

    Currently, there is a renewed interest in common dietaries and plant-based traditional medicines for the prevention and treatment of cancer. In the search for potential anticancer agents from natural sources, ursolic acid (UA), a pentacyclic triterpenoid widely found in various medicinal herbs and fruits, exhibits powerful biological effects including its attractive anticancer activity against various types of cancer cells. However, the limited solubility, rapid metabolism and poor bioavailab...

  1. Novel cyano- and N-isopropylamidino-substituted derivatives of benzo[b]thiophene-2-carboxanilides and benzo[b]thieno[2,3-c]quinolones: synthesis, photochemical synthesis, crystal structure determination, and antitumor evaluation. 2.

    Science.gov (United States)

    Jarak, Ivana; Kralj, Marijeta; Suman, Lidija; Pavlović, Gordana; Dogan, Jasna; Piantanida, Ivo; Zinić, Mladen; Pavelić, Kresimir; Karminski-Zamola, Grace

    2005-04-01

    Derivatives of 3-chlorobenzo[b]thiophene-2-carboxanilides and their "cyclic" analogues benzo[b]thieno[2,3-c]quinolones were synthesized. Spectroscopic study of the interactions of some representatives of "cyclic" derivatives and their "acyclic" precursors with ds-DNA/RNA supported strong intercalative binding of the former and weak nonintercalative binding of the latter group of compounds. All tested compounds showed a certain antiproliferative effect on a series of human tumor cells and on a normal cell line. Among the compounds, those with one amidino-substituent have shown the best effect. The most active benzo[b]thieno[2,3-c]quinolones induced apparent S and G2/M arrests of the cell cycle, which resulted in apoptosis. These results strongly suggest that the compounds may act as topoisimerase "poisons", which is in good agreement with their intercalative mode of binding to ds-DNA/RNA, in contrast to the studied "acyclic"group of derivatives. 6a and 6d showed the best selectivity by inhibiting the growth of tumor cells but not of normal fibroblasts.

  2. Oxidation of quinolones with peracids (an in situ EPR study).

    Science.gov (United States)

    Staško, Andrej; Milata, Viktor; Barbieriková, Zuzana; Brezová, Vlasta

    2014-01-01

    4-Oxoquinoline derivatives (quinolones) represent heterocyclic compounds with a variety of biological activities, along with interesting chemical reactivity. The quinolone derivatives possessing secondary amino hydrogen at the nitrogen of the enaminone system are oxidized with 3-chloroperbenzoic acid to nitroxide radicals in the primary step while maintaining their 4-pyridone ring. Otherwise, N-methyl substituted quinolones also form nitroxide radicals coupled with the opening of the 4-pyridone ring in a gradual oxidation of the methyl group via the nitrone-nitroxide spin-adduct cycle. This was confirmed in an analogous oxidation using N,N-dimethylaniline as a model compound. N-Ethyl quinolones in contrast to its N-methyl analog form only one nitroxide radical without a further degradation.

  3. Synthesis, characterization, molecular modeling, and potential antimicrobial and anticancer activities of novel 2-aminoisoindoline-1,3-dione derivatives.

    Science.gov (United States)

    Ahmed, Hany Emary Ali; Abdel-Salam, Hassan A; Shaker, Mohamed A

    2016-06-01

    In an effort to establish new drug candidates with improved antimicrobial and anticancer activities, we report here synthesis, molecular modeling, and in vitro biological evaluation of novel substituted N-amino phthalamide derivatives (3a-b, 4a-b, 5a-j, and 6). Structures of the newly synthesized compounds were described by IR, (1)H &(13)CNMR and LC-MS spectral data. The novel compounds were evaluated for their antibacterial activity against four types of Gm+ve and two for Gm-ve types, and antifungal activity against three fungi microorganisms by well diffusion method. Of these novel compounds, Schiff bases showed mostly promising antibacterial activity compared to reference drugs. A successful step was done for explanation of their mode of action through molecular docking of most active molecules at DNA gyrase B enzyme and further were biologically tested. Moreover, the antiproliferative activity was tested against two human carcinoma cell lines (Human colon carcinoma (HCT-116) and human breast adenocarcinoma (MCF-7)) showing promising anticancer activity compared to doxorubicin drug. The data from structure-activity relationship (SAR) analysis revealed that the lypophilic properties of these compounds might be essential parameter for their activity and suggest that 2-amino phthalamide scaffold derivatives 5g and 5h exhibited good antimicrobial and anticancer activities and might used as leads for further optimization.

  4. Potentiating effect of UVA irradiation on anticancer activity of Carboplatin derivatives involving 7-azaindoles.

    Directory of Open Access Journals (Sweden)

    Pavel Štarha

    Full Text Available The moderate-to-high in vitro cytotoxicity against ovarian A2780 (IC50 = 4.7-14.4 μM, prostate LNCaP (IC50 = 18.7-30.8 μM and prostate PC-3 (IC50 = 17.6-42.3 μM human cancer cell lines of the platinum(II cyclobutane-1,1'-dicarboxylato complexes [Pt(cbdc(naza2] (1-6; cbdc = cyclobutane-1,1'-dicarboxylate(2-; naza = halogeno-substituted 7-azaindoles, derived from the anticancer metallodrug carboplatin, are reported. The complexes containing the chloro- and bromo-substituted 7-azaindoles (1, 2, and 4-6 showed a significantly higher (p < 0.05 cytotoxicity against A2780 cell line as compared to cisplatin used as a reference drug. Addition of the non-toxic concentration (5.0 μM of L-buthionine sulfoximine (L-BSO, an effective inhibitor of γ-glutamylcysteine synthase markedly increases the in vitro cytotoxicity of the selected complex 3 against A2780 cancer cell line by a factor of about 4.4. The cytotoxicity against A2780 and LNCaP cells, as well as the DNA platination, were effectively enhanced by UVA light irradiation (λmax = 365 nm of the complexes, with the highest phototoxicity determined for compound 3, resulting in a 4-fold decline in the A2780 cells viability from 25.1% to 6.1%. The 1H NMR and ESI-MS experiments suggested that the complexes did not interact with glutathione as well as their ability to interact with guanosine monophosphate. The studies also confirmed UVA light induced the formation of the cis [Pt(H2O2(cbdc`(naza] intermediate, where cbdc` represents monodentate-coordinated cbdc ligand, which is thought to be responsible for the enhanced cytotoxicity. This is further supported by the results of transcription mapping experiments showing that the studied complexes preferentially form the bifunctional adducts with DNA under UVA irradiation, in contrast to the formation of the less effective monofunctional adducts in dark.

  5. Use of antibiotics and about quinolones in veterinary therapy (ro

    Directory of Open Access Journals (Sweden)

    Crina L. Mosneang

    2012-12-01

    Full Text Available In Romania are being done extensively efforts in the veterinarians education to emphasize the importance and the European regulations familiar behavior, relating to veterinary drugs prescribing, the issues of residues, of antibacterial resistance and of judicious use of the veterinary conditionigs. In this respect, the present synthesis presents an overview, a useful and necessary bibliographical remembrance to veterinary practitioner about antibiotics and quinolones in particular. Are summarized: bacterial antagonism, methods for studying the effectiveness of antibiotics, the mode of action of antibiotics, the phenomenon of resistance to antibiotics and toxic secondary phenomena caused by antibiotics, continued by information about quinolone-carbonic acid derivatives (quinolones them action mechanism, classification and presentation of the main representatives, indications and contraindications, etc. Referate is conceived in two parts about antibiotics and about quinolones.

  6. Perspectives of Benzimidazole Derivatives as Anticancer Agents in the New Era.

    Science.gov (United States)

    Yadav, Snehlata; Narasimhan, Balasubramanian; Kaur, Harmeet

    2016-01-01

    Cancer is one of the deadliest diseases nowadays and is a great topic for research as the challenging task is to develop new entities with selectivity towards cancerous cells. Heterocyclic compounds are of great importance in medicinal chemistry as they possess an extensive range of therapeutic applications. Benzimidazole is one such important heterocyclic organic compound having structural analogy to nucleotides found in human body and hence is an important pharmacophore in medicinal chemistry. A variety of marketed drugs containing benzimidazole are thiabendazole, flubendazole (anthelmintic), astmizole (antihistaminic), lansoprazole and omeprazole (antiulcerative). In the light of the above facts, this review is an attempt to summarize the collective contributions from the authors around the world in the field of anticancer agents. This review highlights synthetic schemes and anticancer activity results of the research done in the past years.

  7. Evaluation of the anticancer activities of two fungal polycyclic ethanones, alternethanoxins A and B, and two of their derivatives.

    Science.gov (United States)

    Bury, Marina; Punzo, Biancavaleria; Berestetskiy, Alexander; Lallemand, Benjamin; Dubois, Jacques; Lefranc, Florence; Mathieu, Véronique; Andolfi, Anna; Kiss, Robert; Evidente, Antonio

    2011-01-01

    Alternethanoxins A (1) and B (2) are fungal phytotoxins that are produced by Alternaria sonchi and have been recently characterized as new polycyclic ethanones. Triacetyl (3) and dimethyl (4) derivatives of compound 1 were evaluated together with alternethanoxins for their in vitro growth inhibitory activities in five human and one mouse cancer cell lines in comparison to the reference compound temozolomide (TMZ). Compounds 1-4 and TMZ displayed similar growth inhibitory activities, and these anticancer activities were equivalent in cancer cell lines that display certain levels of resistance to pro-apoptotic stimuli and those that are sensitive to pro-apoptotic stimuli. Of the six cancer cell lines under study, the human esophageal cancer cell line OE21 was the most sensitive to the four polycyclic ethanones. Computer-assisted phase-contrast microscopy (quantitative videomicroscopy) revealed that compounds 1, 2 and 4 displayed cytostatic rather than cytotoxic growth inhibitory effects, while compound 3 appeared to have cytotoxic effects. Thus, this study creates a stimulus for further structure-activity investigations with respect to the anticancer activities of compounds belonging to the alternethanoxin group. The observed toxicity does not seem to be affected by the stereochemistry of C-6 of the B ring, the presence of a hydroxy group at C-1 or the presence of a furan ring joining rings A and C in alternethanoxin B. The anticancer activity (cytostatic versus cytotoxic) of this type of compound could be affected by the chemical moieties present at the hydroxy groups at C-4 and C-6, as was observed for the cytostatic and cytotoxic activities of derivatives 4 and 3, respectively.

  8. Spectroscopic and structural studies of quinoline derivatives—II. Forrier transform i.r. spectroscopy. 1. Rotational isomerism in 3-ethoxycarbonyl-4(1H)-quinolone and some of its substituted derivatives,

    Science.gov (United States)

    Mirek, Julian; Urbanek, Zbigniew H.

    Rotational isomerism associated with internal rotation about the ring carbon(3)-ester carbonyl carbon single bond in a series of 3-ethoxycarbonyl-4(1H)-quinolones have been investigated spectroscopically in the solid state using Fourier transform i.r. and laser Raman spectroscopy. Particular attention is given to the 1700, 1300 and 1100 cm -1 spectral regions related primarily to the vibrations of the CO 2C 2H 5 group. Within these regions rotational isomerism appeared in the compounds examined. The conformational changes are discussed and evidence is reported for occurrence of the unsubstituted compound 1 itself in the solid state at ambient temperature as an equilibrium mixture of both the s-trans ( 1a) and s-cis ( 1b) rotamers (this is in contrast to previous findings), and of its Bz-substituted derivatives.

  9. Photoprocesses in quinolone substituted

    Science.gov (United States)

    Vasilyeva, N. Y.; Vusovich, O. V.

    2002-03-01

    In the present work the analysis of the possible ways of energy degradation of electron excited states of 4-methyl-7- hydxyquinolone-2 (Q) and its protolytic species is presented (Figure 1); a ratio of radiative and nonradiative channels of deactivation of energy of electronic excitation is established; constants of photophysical processes (internal and intercrossing conversion), proceeding after act of absorption of light are designed. Study of exited state intramolecular proton transfer (ESIPT) in quinolones is interesting as a source of information on the relative importance of these processes in the photophysics and photochemistry of such molecular systems.

  10. N-Substituted piperazinyl quinolones as potential cytotoxic agents: structure-activity relationships study.

    Science.gov (United States)

    Foroumadi, Alireza; Emami, Saeed; Rajabalian, Saeed; Badinloo, Marziyeh; Mohammadhosseini, Negar; Shafiee, Abbas

    2009-03-01

    As part of a continuing search for new potential anticancer candidates in the piperazinyl quinolone series, the cytotoxicity evaluation of new N-substituted piperazinyl quinolones was of our interest. The growth inhibitory activities of 12 new compounds, namely N-[2-(5-chlorothiophen-2-yl)-2-oxoethyl] and N-[2-(5-chlorothiophen-2-yl)-2-oxyiminoethyl] piperazinyl quinolones 1-12 were determined against six cancer cell lines using MTT colorimetric assay. Preliminary screening showed that most of the new N-[2-(5-chlorothiophen-2-yl)ethyl]piperazinyl quinolones 4-12 containing (un)substituted oxime moiety showed significant cytotoxic activity and the modification of functionality on ethyl spacer produced a relatively minor change of activity. Thus, in the piperazinyl quinolone series, cytotoxic activity can be positively modulated through the introduction of 2-(5-chlorothiophen-2-yl)ethyl residue on the piperazine ring. The results revealed that the introduction of 2-(5-chlorothiophen-2-yl)ethyl moiety on the piperazine ring of quinolone antibacterials (ciprofloxacin, norfloxacin and enoxacin) changes the biological profile of piperazinyl quinolones from antibacterials to cytotoxic agents.

  11. Molecular modeling studies and synthesis of novel quinoxaline derivatives with potential anticancer activity as inhibitors of c-Met kinase.

    Science.gov (United States)

    Abbas, Hebat-Allah S; Al-Marhabi, Aisha R; Eissa, Sally I; Ammar, Yousry A

    2015-10-15

    In an effort to develop potent anti-cancer agents, we have synthesized some substituted quinoxaline derivatives. Reaction of 6-bromo-3-methylquinoxalin-2(1H)-one 1 with aromatic aldehydes furnished the styryl derivatives 2a-e. Alkylation of 1 with ethyl chloroacetate produced the N-alkyl derivatives 3. Hydrazinolysis of the ester derivative 3 with hydrazine hydrate afforded the hydrazide derivative 4. In addition, chlorination of 1 with phosphorus oxychloride afforded the 2-chloro derivative 5 which was used as a key intermediate for the synthesis of substituted quinoxaline derivatives 6-8, N-pyrazole derivative 9, tetrazolo[1,5-a]quinoxaline derivative 10 and Schiff base derivatives 13, 15 via reaction with several nucleophiles reagents. Docking methodologies were used to predict their binding conformation to explain the differences of their tested biological activities. All the tested compounds were screened in vitro for their cytotoxic effect on three tumor cell lines. Some new quinoxaline derivatives were studied as inhibitors of c-Met kinase, a receptor associated with high tumor grade and poor prognosis in a number of human cancers. Compounds 2e, 4, 7a, 12a, 12b and 13 showed the highest binding affinity with CDOCKER energy score, while showed the lowest IC50 values against three types of cancer cell lines. It is worth to mention that, compounds 2e, 7a, 12b and 13 showed comparable inhibition activity to the reference drug, while compounds 4 and 12a showed a more potent inhibition activity than Doxorubicin.

  12. In Silico Screening, Synthesis and In Vitro Evaluation of Some Quinazolinone and Pyridine Derivatives as Dihydrofolate Reductase Inhibitors for Anticancer Activity

    Directory of Open Access Journals (Sweden)

    A. G. Nerkar

    2009-01-01

    Full Text Available Dihydrofolate reductase (DHFR is the important target for anticancer drugs belonging to the class of antimetabolites as the enzyme plays important role in the de novo purine synthesis. We here report the in silico screening to obtain best fit molecules as DHFR inhibitors, synthesis of some ʻbest fitʼ quinazolinone from 2-phenyl-3-(substituted-benzilidine-amino quinazolinones (Quinazolinone Shiff's bases QSB1-5 and pyridine-4-carbohydrazide Shiff's bases (ISB1-5 derivatives and their in vitro anticancer assay. Synthesis of the molecules was performed using microwave assisted synthesis. The structures of these molecules were elucidated by IR and 1H-NMR. These compounds were then subjected for in vitro anticancer evaluation against five human cancer cell-lines for anticancer cyto-toxicity assay. Methotrexate (MTX was used as standard for this evaluation to give a comparable inhibition of the cell proliferation by DHFR inhibition. Placlitaxel, adriamycin and 5-fluoro-uracil were also used as standard to give a comparable activity of these compounds with other mechanism of anticancer activity. ISB3 (4-(N, N-dimethyl-amino-phenyl Schiff''s base derivative of pyridine carbohydrazide showed equipotent activity with the standards used in in vitro anticancer assay as per the NCI (National Cancer Institute guidelines.

  13. Glycyrrhetinic Acid and Its Derivatives: Anti-Cancer and Cancer Chemopreventive Properties, Mechanisms of Action and Structure- Cytotoxic Activity Relationship.

    Science.gov (United States)

    Roohbakhsh, Ali; Iranshahy, Milad; Iranshahi, Mehrdad

    2016-01-01

    The anti-cancer properties of liquorice have been attributed, at least in part, to glycyrrhizin (GL). However, GL is not directly absorbed through the gastrointestinal tract. It is hydrolyzed to 18-β-glycyrrhetinic acid (GA), the pharmacologically active metabolite, by human intestinal microflora. GA exhibits remarkable cytotoxic and anti-tumor properties. The pro-apoptotic targets and mechanisms of action of GA have been extensively studied over the past decade. In addition, GA is an inexpensive and available triterpene with functional groups (COOH and OH) in its structure, which make it an attractive lead compound for medicinal chemists to prepare a large number of analogues. To date, more than 400 cytotoxic derivatives have been prepared on the basis of GA scaffold, including 128 cytotoxic derivatives with IC50 values less than 30 µM. Researchers have also succeeded in synthesizing very potent cytotoxic derivatives with IC50s ≤ 1 µM. Studies have shown that the introduction of a double bound at the C1-C2 position combined with an electronegative functional group, such as CN, CF3 or iodine at C2 position, and the oxidation of the hydroxyl group of C3 to the carbonyl group, significantly increased cytotoxicity. This review describes the cytotoxic and anti-tumor properties of GA and its derivatives, targets and mechanisms of action and provides insight into the structure-activity relationship of GA derivatives.

  14. Synthesis and Anticancer Activity of Some New S-Glycosyl and S-Alkyl 1,2,4-Triazinone Derivatives

    Directory of Open Access Journals (Sweden)

    Hosam A. Saad

    2011-07-01

    Full Text Available A series of S-glycosyl and S-alkyl derivatives of 4-amino-3-mercapto-6-(2-(2-thienylvinyl-1,2,4-triazin-5(4H-one (1 were synthesized using different halo compounds such as preacetylated sugar bromide, 4-bromobutylacetate, 2-acetoxyethoxy-methyl bromide, 3-chloropropanol, 1,3-dichloro-2-propanol, epichlorohydrin, allyl bromide, propargyl bromide, phthalic and succinic acids in POCl3. The structures of the synthesized compounds have been deduced from their elemental analysis and spectral (IR, 1H-NMR, and 13C-NMR data. Some of the synthesized compounds were screened as anticancer agents. Significant anticancer activities were observed in vitro for some members of the series, and compounds 4-Amino-3-(3-hydroxypropylthio-6-(2-(2-thienylvinyl-1,2,4-triazin-5(4H-one (12 and 3-(4-Oxo-3-(2-(2-thienylvinyl-4H-[1,3,4]thiadiazolo-[2,3-c][1,2,4]tr-iazin-7-ylpropanoic acid (18 are active cytotoxic agents against different cancer cell lines.

  15. The Madeira Archipelago as a significant source of marine-derived actinomycete diversity with anticancer and antimicrobial potential

    Directory of Open Access Journals (Sweden)

    Alejandra Prieto-Davo

    2016-10-01

    Full Text Available Marine-derived actinomycetes have demonstrated an ability to produce novel compounds with medically relevant biological activity. Studying the diversity and biogeographical patterns of marine actinomycetes offers an opportunity to identify genera that are under environmental pressures, which may drive adaptations that yield specific biosynthetic capabilities. The present study describes research efforts to explore regions of the Atlantic Ocean, specifically around the Madeira Archipelago, where knowledge of the indigenous actinomycete diversity is scarce. A total of 400 actinomycetes were isolated, sequenced and screened for antimicrobial and anticancer activities. The three most abundant genera identified were Streptomyces, Actinomadura and Micromonospora. Phylogenetic analyses of the marine OTUs isolated indicated that the Madeira Archipelago is a new source of actinomycetes adapted to life in the ocean. Phylogenetic differences between offshore (>100m from shore and nearshore (<100m from shore populations illustrates the importance of sampling offshore in order to isolate new and diverse bacterial strains. Novel phylotypes from chemically rich marine actinomycete groups like MAR4 and the genus Salinispora were isolated. Anticancer and antimicrobial assays identified Streptomyces, Micromonospora and Salinispora as the most biologically active genera. This study illustrates the importance of bioprospecting efforts at unexplored regions of the ocean to recover bacterial strains with the potential to produce novel and interesting chemistry.

  16. The Madeira Archipelago As a Significant Source of Marine-Derived Actinomycete Diversity with Anticancer and Antimicrobial Potential

    Science.gov (United States)

    Prieto-Davó, Alejandra; Dias, Tiago; Gomes, Sofia E.; Rodrigues, Sara; Parera-Valadez, Yessica; Borralho, Pedro M.; Pereira, Florbela; Rodrigues, Cecilia M. P.; Santos-Sanches, Ilda; Gaudêncio, Susana P.

    2016-01-01

    Marine-derived actinomycetes have demonstrated an ability to produce novel compounds with medically relevant biological activity. Studying the diversity and biogeographical patterns of marine actinomycetes offers an opportunity to identify genera that are under environmental pressures, which may drive adaptations that yield specific biosynthetic capabilities. The present study describes research efforts to explore regions of the Atlantic Ocean, specifically around the Madeira Archipelago, where knowledge of the indigenous actinomycete diversity is scarce. A total of 400 actinomycetes were isolated, sequenced, and screened for antimicrobial and anticancer activities. The three most abundant genera identified were Streptomyces, Actinomadura, and Micromonospora. Phylogenetic analyses of the marine OTUs isolated indicated that the Madeira Archipelago is a new source of actinomycetes adapted to life in the ocean. Phylogenetic differences between offshore (>100 m from shore) and nearshore (< 100 m from shore) populations illustrates the importance of sampling offshore in order to isolate new and diverse bacterial strains. Novel phylotypes from chemically rich marine actinomycete groups like MAR4 and the genus Salinispora were isolated. Anticancer and antimicrobial assays identified Streptomyces, Micromonospora, and Salinispora as the most biologically active genera. This study illustrates the importance of bioprospecting efforts at unexplored regions of the ocean to recover bacterial strains with the potential to produce novel and interesting chemistry. PMID:27774089

  17. Polyketide Derivatives from Annona muricata Linn Leaves as Potencial Anticancer Material by Combination Treatment With Doxorubicin on Hela Cell Line

    Science.gov (United States)

    Artanti, A. N.; Astirin, O. P.; Prayito, A.; Widiyaningsih, R. F.; Prihapsara, F.

    2017-02-01

    One of the compounds found effication as an anticancer agent on cervical cancer is acetogenin, a polyketide compound that is abundant in Annona muricata L. leaves. This study has been done to examine polyketide derivatives was isolated from Annona muricata L. which has potency to induce apoptosis by p53 expression on hela cell line. An approach recently develop to overcome side effect of chemoterapeutic agent is used of combined chemoterapeutic agent, i.e doxorubicin. The determination of cytotoxic combination activity from polyketide derivative and doxorubicin was evaluated using MTT assay to obtain the value of CI (combination index). The expression of p53 profile was evaluated by immunohistochemistry on hela cell line. Data analysis showed that combination of polyketide derivative from Annona muricata L. (38,5 µg/ml) and doxorubicin with all of concentration performed synergistic effect on hela cell line with CI value from 0,33 – 0,65. The analysis on immucytochemistry showed that polyketide derivative from Annona muricata L. leaves could enhance p53 pathway significantly on hela cell line.

  18. Design and synthesis of novel 1,2,3-triazole derivatives of coronopilin as anti-cancer compounds.

    Science.gov (United States)

    Khazir, Jabeena; Hyder, Irfan; Gayatri, J Laxmi; Prasad Yandrati, Leela; Nalla, Naresh; Chasoo, Gousia; Mahajan, Ajay; Saxena, A K; Alam, M S; Qazi, G N; Sampath Kumar, Halmuthur M

    2014-07-23

    A series of 1,2,3-triazole coronopilin congeners have been designed and synthesized by employing click chemistry approach starting from parthenin and evaluated for their cytotoxicity against a panel of six human cancer cell lines (PC-3, THP-1, HCT-15, HeLa, A-549 and MCF-7). While many compounds exhibited significant anticancer activity, compound 3a, was found to be the most promising analogue in this series with IC50 values of 3.1 μM on PC-3 cell line. Flow-cytometric studies showed that 1,2,3-triazole derivative-3a induce dose dependent apoptosis in the sub G1 phase. This lead molecule-3a was further studied for NF-κB (p65) transcription factor inhibitory activity using Elisa and western blotting analysis which confirmed concentration dependent inhibitory activity against NF-κB, p65 with 80% inhibition in 24 h at 100 μM.

  19. Effects on the sodium channel of some new cardiotonic drugs: the 4-, 5-, and 6-pyridyl-2(1H)-quinolone derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Grima, M.; Beguin, M.F.; Millanvoye-Van Brussel, E.M.; Decker, N.; Schwartz, J.

    1988-09-01

    To study the action of some new cardiotonic drugs, the 4-, 5-, and 6-pyridyl-2(1H)-quinolone series, on the fast Na+ channel, we compared the effects of eight compounds of this series and milrinone on /sup 22/Na uptake in rat brain synaptosomes and in rat heart muscle cells in culture. The action of tetrodotoxin, a specific Na+ channel blocker, on the positive inotropic effect of these compounds on guinea pig atria was also examined. The new positive inotropic agents enhance /sup 22/Na uptake in synaptosomes in a dose-dependent manner. The activities, expressed as percentage of the maximum activity of protoveratrine B, a classic Na+ channel agonist, reached 70% for milrinone, 60% for compound 7, 57% for compound 6, and less than 50% for the other drugs. For compound 8, but not for milrinone, it was possible to observe a stimulatory effect of the /sup 22/Na uptake on heart muscle cells in culture. Tetrodotoxin (1 and 100 microM) inhibited the stimulatory effects of the inotropic drugs on both preparations. The positive inotropic activities of protoveratrine B, milrinone, and compounds 5 and 8, in guinea pig atria, were inhibited by tetrodotoxin. The affinity and the activity of the other compounds were unchanged in the presence of tetrodotoxin. Our results showed that the stimulation of Na+ influx through the fast Na+ channel might represent a part of the mechanism of action of the inotropic effect of some new cardiotonic drugs.

  20. Anticancer and antimicrobial activity of mangrove derived fungi Hypocrea lixii VB1

    Institute of Scientific and Technical Information of China (English)

    B.ValentinBhimba; D.A.AgnelDeforaFranco; JibiMerinMathew; GeenaMaryJose; ElsaLyciasJoel; M.Thangaraj

    2012-01-01

    AIM:Mangrove is one of the oldest living tree species and its leaves are among the most extensively studied botanicals in use today.Scientific research throughout the world has found evidence to support the fact that its foliar extracts have great potential against human microbial pathogens.This study highlights the isolation of foliar fungi from Rhizophora mucronata,Avicenna officialis and Avicenna marina.METHOD:It was isolated in Sabouroud's Dextrose Agar and mass cultivation was done in Sabouroud's Dextrose broth.RESULTS:The ethyl acetate extract showed maximum antibacterial activity which inturn checked for different concentration against bacterial pathogens and anticancer activity for Hep2 and MCF-7cell line in vitro.The DNA was isolated from the fungi and the ITS region of 5.8 s RNA was sequenced and assigned to new species as they are separated from the type strains phylogenetic neighbors by sequence similarities.CONCLUSION:This preliminary screening of fungal endophytes revealed their potential to yield potent bioactive compounds for drug discovery programmes.

  1. Greco-Arab and Islamic Herbal-Derived Anticancer Modalities: From Tradition to Molecular Mechanisms

    Directory of Open Access Journals (Sweden)

    Hilal Zaid

    2012-01-01

    Full Text Available The incidence of cancer is increasing in the developed countries and even more so in developing countries parallel to the increase in life expectancy. In recent years, clinicians and researchers advocate the need to include supportive and palliative care since the establishment of the diagnosis and throughout the duration of treatment, with the goal of improving patients' quality of life. This patient-centered approach in supportive care is also shared by various traditional and complementary medicine approaches. Traditional Arab-Islamic medicine offers a variety of therapeutic modalities that include herbal, nutritional, and spiritual approaches. Physicians and scholars, such as Avicenna (980–1037, Rhazes (965–915, Al Zahrawi (936–1013, and Ibn al Nafis (1218–1288 referred to cancer etiology in various medicinal texts and suggested both preventive and therapeutic remedies to alleviate suffering. This review presents research data related to the anticancer activities of herbs used in Arab-Islamic medicine and allude to their potential role in improving the quality of life of cancer patients.

  2. A General Synthetic Procedure for 2-chloromethyl-4(3H-quinazolinone Derivatives and Their Utilization in the Preparation of Novel Anticancer Agents with 4-Anilinoquinazoline Scaffolds

    Directory of Open Access Journals (Sweden)

    Ying-Lan Zhao

    2010-12-01

    Full Text Available In our ongoing research on novel anticancer agents with 4-anilinoquinazoline scaffolds, a series of novel 2-chloromethyl-4(3H-quinazolinones were needed as key intermediates. An improved one-step synthesis of 2-chloromethyl-4(3H-quinazolinones utilizing o-anthranilic acids as starting materials was described. Based on it, 2-hydroxy-methyl-4(3H-quinazolinones were conveniently prepared in one pot. Moreover, two novel 4-anilinoquinazoline derivatives substituted with chloromethyl groups at the 2-position were synthesized and showed promising anticancer activity in vitro.

  3. Synthesis and anticancer activity evaluation of some benzothiazole-piperazine derivatives.

    Science.gov (United States)

    Gurdal, Enise Ece; Buclulgan, Ebru; Durmaz, Irem; Cetin-Atalay, Rengul; Yarim, Mine

    2015-01-01

    Synthesis, characterization and cytotoxic activities of ten benzothiazole-piperazine derivatives were reported. In vitro cytotoxic activities of compounds were screened against hepatocellular (HUH-7), breast (MCF-7) and colorectal (HCT-116) cancer cell lines by sulphorhodamine B assay. Based on the GI50 values of the compounds, most of the benzothiazole-piperazine derivatives are active against HUH-7, MCF-7 and HCT-116 cancer cell lines. Aroyl substituted compounds 1h and 1j were found to be the most active derivatives. In addition, further investigation of compounds 1h and 1j by Hoechst staining and FACS revealed that these compounds cause apoptosis by cell cycle arrest at subG1 phase.

  4. Chemical properties and mechanisms determining the anti-cancer action of garlic-derived organic sulfur compounds.

    Science.gov (United States)

    Cerella, Claudia; Dicato, Mario; Jacob, Claus; Diederich, Marc

    2011-03-01

    Organic sulfur compounds (OSCs) derived from plants, fungi or bacteria can serve as chemopreventive and/or chemotherapeutic agents and have been attracting medical and research interest as a promising source for novel anti-cancer agents. Garlic, which has long been used as a medicinal plant in different cultures due to its multiple beneficial effects, contains a consistent number of OSCs, the majority of which are currently under investigation for their biological activities. Experimental animal and laboratory studies have shown strong evidence that garlic OSCs may affect cancer cells by promoting early mitotic arrest followed by apoptotic cell death without affecting healthy cells. The ability of OSCs to hinder cancer cell proliferation and viability tightly correlates with the length of the sulfur chain. Current data support a mechanism of mitotic arrest of cancer cells due to the alteration of the microtubule network, possibly as a consequence of the high reactivity of sulfur atoms against the thiol groups of different cellular macromolecules controlling crucial regulatory functions. Taken together, these findings indicate a promising potential for the use of garlic-derived sulfur compounds in chemoprevention and chemotherapy.

  5. Theoretical study of amino derivatives and anticancer platinum drug grafted on various carbon nanostructures.

    Science.gov (United States)

    Kraszewski, S; Duverger, E; Ramseyer, C; Picaud, F

    2013-11-07

    Density functional theory calculations with van der Waals approximation have been conducted to analyze the functionalization of various carbon-based nanostructures (fullerene, metallic, and semi-conducting nanotubes) with amino derivative groups. The results obtained with azomethine, show the formation of a five membered ring on fullerenes, and on nanotubes consistent with experimental observations. The attachment of an azomethine plus subsequent drug like a Pt(IV) complex does not perturb the cycloaddition process. Moreover, all theoretical results show that the length of different amino derivatives with subsequent Pt(IV) complex does not affect the complexed therapeutic agent when it is attached onto these carbon-based nanostructures.

  6. Polycyclic Aromatic Compounds as Anticancer Agents: Synthesis and Biological Evaluation of Methoxy Dibenzofluorene Derivatives

    Directory of Open Access Journals (Sweden)

    Bimal Krishna Banik

    2014-08-01

    Full Text Available Synthesis of a new methoxy dibenzofluorene through alkylation, cyclodehydration and aromatization in a one-pot operation is achieved for the first time. Using this hydrocarbon, a few derivatives are prepared through aromatic nitration, catalytic hydrogenation, coupling reaction with a side chain and reduction. The benzylic position of this hydrocarbon with the side chain is oxidized and reduced. Some of these derivatives have demonstrated excellent antitumor activities in vitro. This study confirms antitumor activity depends on the structures of the molecules.

  7. Synthesis, in vitro anticancer evaluation and in silico studies of novel imidazo[2,1-b]thiazole derivatives bearing pyrazole moieties.

    Science.gov (United States)

    Ali, Ahmed R; El-Bendary, Eman R; Ghaly, Mariam A; Shehata, Ihsan A

    2014-03-21

    A series of imidazo[2,1-b]thiazoles bearing pyrazole moieties 4-6(a-c) was synthesized through the reaction of 6-hydrazinylimidazo[2,1-b]thiazoles 3a-c with different β-dicarbonyl compounds. Eleven compounds were screened at the National Cancer Institute (NCI), USA for anticancer activity at a single dose (10 μM). The in vitro anticancer evaluation revealed that compounds 2a and 4-6(a) exhibited increased potency towards CNS SNB-75 and Renal UO-31 cancer cell lines. COMPARE analyses showed strong to considerable correlations with rapamycin (mTOR inhibitor). The results of assessment of toxicities, druglikeness, and drug score profiles of compounds 2a and 4-6(a) are promising. Some of the target compounds showed good docking scores with potential anticancer targets, chosen based on pharmacophore mapping of the established derivatives.

  8. Synthesis and biological evaluation of nitric oxide-releasing matrine derivatives as anticancer agents

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A series of furoxan-based nitric oxide-releasing matrine derivatives(10a-f) were synthesized.The biological evaluation showed that compounds 10a,10b,10e and 10f had stronger cytotoxic activities than 5-fluorouracil against human hepatoma cells(HepG2) in vitro.

  9. Chloramphenicol Derivatives as Antibacterial and Anticancer Agents: Historic Problems and Current Solutions

    Directory of Open Access Journals (Sweden)

    George P. Dinos

    2016-06-01

    Full Text Available Chloramphenicol (CAM is the D-threo isomer of a small molecule, consisting of a p-nitrobenzene ring connected to a dichloroacetyl tail through a 2-amino-1,3-propanediol moiety. CAM displays a broad-spectrum bacteriostatic activity by specifically inhibiting the bacterial protein synthesis. In certain but important cases, it also exhibits bactericidal activity, namely against the three most common causes of meningitis, Haemophilus influenzae, Streptococcus pneumoniae and Neisseria meningitidis. Resistance to CAM has been frequently reported and ascribed to a variety of mechanisms. However, the most important concerns that limit its clinical utility relate to side effects such as neurotoxicity and hematologic disorders. In this review, we present previous and current efforts to synthesize CAM derivatives with improved pharmacological properties. In addition, we highlight potentially broader roles of these derivatives in investigating the plasticity of the ribosomal catalytic center, the main target of CAM.

  10. New hydroxamic acid derivatives of fluoroquinolones: synthesis and evaluation of antibacterial and anticancer properties.

    Science.gov (United States)

    Rajulu, Gavara Govinda; Bhojya Naik, Halehatty Seephya; Viswanadhan, Abhilash; Thiruvengadam, Jayaraman; Rajesh, Kondodiyil; Ganesh, Sambasivam; Jagadheshan, Hiriyan; Kesavan, Poonimangadu Koppolu

    2014-01-01

    A series of new hydroxamic acid derivatives (6a-f) at C-3 position of fluoroquinolones were designed and synthesized through multistep synthesis. The design concept involved replacement of the 3-carboxylic acid in fluoquinolones with hydroxamic acid as an acid mimicking group. The synthetic work employed in this work provides a good example for the synthesis of pure hydroxamic acid based fluoroquinolones. The synthesized compounds were characterized by (1)H-NMR, electrospray ionization (ESI)-MS and IR. The new compounds were tested for their in vitro antimicrobial and anti-proliferative activity. Out of the six derivatives, compound 6e exhibited moderate antibacterial activity by inhibiting the growth of Escherichia coli and Klebsiella pneumoniae (MIC: 4.00-8.00 µg/mL). Compounds 6b and 6f displayed good growth inhibition against A549 Lung adenocarcinoma and HCT-116 Colon carcinoma cell lines.

  11. Recent developments regarding the use of thieno[2,3-d]pyrimidin-4-one derivatives in medicinal chemistry, with a focus on their synthesis and anticancer properties.

    Science.gov (United States)

    Bozorov, Khurshed; Zhao, Jiang-Yu; Elmuradov, Burkhon; Pataer, Apar; Aisa, Haji A

    2015-09-18

    It is generally understood that the antitumor properties of synthetic heterocyclic compounds are among the most powerful properties that can be made use in medicinal chemistry. More specifically, their substantial cytotoxic effects against different types of human tumor cells, in addition to their roles as enzymes or receptors for various kinase inhibitors, make them critically important. In recent years, thieno[2,3-d]pyrimidin-4-one derivatives (TPs), which are analogs of quinazoline alkaloids, have frequently attracted the interest of medicinal chemistry researchers due to their promising anticancer properties. The present study is a review of the latest advances (i.e., since 2006) in TP derivative-related research, with a focus on how such derivatives are synthesized and on their anticancer activities.

  12. The in Vitro Structure-Related Anti-Cancer Activity of Ginsenosides and Their Derivatives

    Directory of Open Access Journals (Sweden)

    Liang Liu

    2011-12-01

    Full Text Available Panax ginseng has long been used in Asia as a herbal medicine for the prevention and treatment of various diseases, including cancer. The current study evaluated the cytotoxic potency against a variety of cancer cells by using ginseng ethanol extracts (RSE, protopanaxadiol (PPD-type, protopanaxatriol (PPT-type ginsenosides fractions, and their hydrolysates, which were prepared by stepwise hydrolysis of the sugar moieties of the ginsenosides. The results showed that the cytotoxic potency of the hydrolysates of RSE and total PPD-type or PPT-type ginsenoside fractions was much stronger than the original RSE and ginsenosides; especially the hydrolysate of PPD-type ginsenoside fractions. Subsequently, two derivatives of protopanaxadiol (1, compounds 2 and 3, were synthesized via hydrogenation and dehydration reactions of compound 1. Using those two derivatives and the original ginsenosides, a comparative study on various cancer cell lines was conducted; the results demonstrated that the cytotoxic potency was generally in the descending order of compound 3 > 20(S-dihydroprotopanaxadiol (2 > PPD (1 > 20(S-Rh2 > 20(R-Rh2 ≈ 20(R-Rg3 ≈ 20(S-Rg3. The results clearly indicate the structure-related activities in which the compound with less polar chemical structures possesses higher cytotoxic activity towards cancer cells.

  13. Novel nitric oxide-releasing spirolactone-type diterpenoid derivatives with in vitro synergistic anticancer activity as apoptosis inducer.

    Science.gov (United States)

    Li, Dahong; Han, Tong; Tian, Kangtao; Tang, Shuang; Xu, Shengtao; Hu, Xu; Wang, Lei; Li, Zhanlin; Hua, Huiming; Xu, Jinyi

    2016-09-01

    Herein, we reported the cytotoxicity, NO-releasing property, and apoptosis induced ability of two series of novel nitric oxide-releasing spirolactone-type diterpenoid derivatives (10a-f and 15a-f). All the title compounds were more potent than oridonin (7) and parent compound (9 or 14) against human tumor Bel-7402, K562, MGC-803 and CaEs-17 cells. SARs were concluded based on above data. Compound 15d exhibited the strongest antiproliferative activity with the IC50 of 0.86, 1.74, 1.16 and 3.75μM, respectively, and could produce high level (above 25μM) of NO at the time point of 60min. Further mechanism evaluation showed that 15d could induce S phase cell cycle arrest and apoptosis at low micromolar concentrations in Bel-7402 cells via mitochondria-related pathways. It was expected that the remarkable biological profile of the synthetic NO-releasing spirolactone-type diterpenoid analogs make them possible as promising candidates for the development of anticancer agents.

  14. Biological evaluation of structurally diverse amaryllidaceae alkaloids and their synthetic derivatives: discovery of novel leads for anticancer drug design.

    Science.gov (United States)

    Evidente, Antonio; Kireev, Artem S; Jenkins, Aaron R; Romero, Anntherese E; Steelant, Wim F A; Van Slambrouck, Severine; Kornienko, Alexander

    2009-04-01

    Twenty-nine Amaryllidaceae alkaloids and their derivatives belonging to the five most common groups, including lycorine, lycorenine, tazettine, crinine, and narciclasine types, were evaluated for antiproliferative, apoptosis-inducing, and anti-invasive activities in vitro. The antiproliferative properties of each test compound are in agreement with those reported in the literature, while the high potency of amarbellisine is reported for the first time. It was also found that with the exception of ungeremine, amarbellisine, and hippeastrine, the antiproliferative effect of the potent compounds is apoptosis mediated. Thus, apoptosis in Jurkat cells was triggered by narciclasine, narciclasine tetraacetate, C10b-R-hydroxypancratistatin, cis-dihydronarciclasine, trans-dihydronarciclasine, lycorine, 1-O-acetyllycorine, lycorine-2-one, pseudolycorine, and haemanthamine. With the exception of narciclasine, lycorine, and haemanthamine, the apoptosis-inducing properties of these compounds are reported for the first time. The collagen type I invasion assay revealed potent anti-invasive properties associated with N-methyllycorine iodide, hippeastrine, clivimine, buphanamine, and narciclasine tetraacetate, all of which were tested at non-toxic concentrations. The anti-invasive activity of buphanamine is particularly promising because this alkaloid is not toxic to cells even at much higher doses. This work has resulted in the identification of several novel leads for anticancer drug design.

  15. Nitro-oxidative Stress Is Involved in Anticancer Activity of 17β-Estradiol Derivative in Neuroblastoma Cells.

    Science.gov (United States)

    Gorska, Magdalena; Kuban-Jankowska, Alicja; Milczarek, Ryszard; Wozniak, Michal

    2016-04-01

    Neuroblastoma is one of the most common childhood malignancies and the primary cause of death from pediatric cancer. Derivatives of 17β-estradiol, 2-methoxyestradiol, as well as selective estrogen receptor modulators, such as fulvestrant, are novel potentially active anticancer agents. In particular, 2-methoxyestradiol is effective in treatment of numerous malignancies, including breast and prostate cancer, Ewing sarcoma, and osteosarcoma. Herein, we treated neuroblastoma SH-SY5Y cells with physiologically and pharmacologically relevant concentrations of 2-methoxyestradiol. We used flow cytometry in order to determine cell viability, cell death, level of nitric oxide and mitochondrial membrane potential. We demonstrated that at pharmacologically relevant concentrations, 2-methoxyestradiol results in induction of apoptosis of neuroblastoma SH-SY5Y cells via nitric oxide generation and reduction of mitochondrial membrane potential. Based on the obtained data, we propose that 2-methoxyestradiol may be a natural modulator of cancer cell death and survival through nitro-oxidative stress-dependent mechanisms. Moreover, the results confirm the efficiency of 2-methoxyestradiol in treatment of neuroblastoma.

  16. Synthesis, evaluation and QSAR studies of 16-(4 & 3,4-substituted) benzylidene androstene derivatives as anticancer agents.

    Science.gov (United States)

    Dubey, S; Kaur, P; Jindal, D P; Satyanarayan, Y D; Piplani, P

    2008-05-01

    In a systematic effort aimed at identifying new steroidal cytotoxic agents with potent antipoliferative activity against cancer cells and developing their QSAR models, series of 4-nitro, 4-isopropyl, 4-methoxy and 3,4-dimethoxy substituted benzylidene androst-5-ene derivatives were synthesized. The selected compounds were evaluated for antineoplastic activity against a panel of three human cell lines-breast, CNS and lungs at NCI, Bethesda, USA. The results presented herein reports that compounds 7, 9, 10, 15,16, 18, 20-25, 30, 32-36 and 44 have been found to be active anticancer agents. The QSAR of 20 compounds was performed separately for each cell line and best-fit QSAR models are developed. The QSAR models obtained have shown significant correlations (r(2) range: 0.9163 to 0.8164) and good predictive performance (q(2) range: 0.8499- 0.6320). The validation of models has also been performed using the test set of compounds 5, 15 and 44.

  17. A novel anticancer diarylurea derivative HL-40 as a multi-kinases inhibitor with good pharmacokinetics in Wistar rats.

    Science.gov (United States)

    Lu, Yu-Yin; Zhao, Cui-Rong; Wang, Rui-Qi; Li, Wen-Bao; Qu, Xian-Jun

    2015-02-01

    HL-40, N-(4-(1-(4-chlorine indazole)) phenyl)-N-(4-chloro-3-three fluorine methyl phenyl) urea, is a novel diarylurea derivative. In this study, we investigated the kinases activities and binding constants, pharmacokinetics of HL-40, and then evaluated its anticancer efficacy by both in vitro and in vivo methods. Enzyme activities assays in vitro were employed to identify eight candidate kinase targets. The competition binding assays against eight candidate kinases suggested that HL-40 showed strong affinity to c-Kit, PDGFRβ and FLT3. The pharmacokinetic studies in Wistar rats showed that HL-40 could maintain high compound concentration and long residence time in the blood circulation. HL-40 possessed strong inhibition activities against 12 human cancer cells. Meanwhile, HL-40 effectively delayed the growth of cancer xenografts without significant toxicity to mice. Based on these in vitro and in vivo results, we suggested that HL-40 might be developed as a potential multi-kinases inhibitor for cancer treatment.

  18. Synthesis and biological evaluation of nitric oxide-releasing sixalkoxyl biphenyl derivatives as anticancer agents

    Institute of Scientific and Technical Information of China (English)

    Xiang Wen Kong; Yi Hua Zhang; Li Dai; Hui Ji; Yi Sheng Lai; Si Xun Peng

    2008-01-01

    A series of novel nitric oxide-donating sixalkoxyl biphenyl derivatives (14a-i)were synthesized by coupling furoxan with alkoxyl biphenyl skeleton using amino acids as the spacers,and their cytotoxicity against HepG2 cells in vitro were evaluated by MTr method.It was found that 14c,14d,14f,14i,14j and 14k showed more potent cytotoxic activities than control 5-fluorouracil.NO release assay of target compounds indicated that the maximum amount of NO released by most active compounds 14c and 14j was about 6 x 10-2μmol/L,whereas 14a and 14h with very weak activity only released NO of 1 x 10-μmol/L.

  19. Novel pyrazole-5-carboxamide and pyrazole-pyrimidine derivatives: synthesis and anticancer activity.

    Science.gov (United States)

    Shi, Jing Bo; Tang, Wen Jian; Qi, Xing Bao; Li, Rong; Liu, Xin Hua

    2015-01-27

    A series of novel pyrazole-5-carboxamide and pyrazole-pyrimidine derivatives were designed and synthesized. All compounds have been screened for their antiproliferative activity against MGC-803, SGC-7901 and Bcap-37 cell lines in vitro. The results revealed that compounds 8a, 8c and 8e exhibited strong inhibitory activity against MGC-803 cell line. The flow cytometric analysis result showed that compound 8e could inhibit MGC-803 proliferation. Some title compounds were tested against telomerase, and compound 8e showed the most potent inhibitory activity with IC50 value at 1.02 ± 0.08 μM. The docking simulation of compound 8e was performed to get the probable binding model, among them, LYS 189, LYS 372, LYS 249 and ASP 254 may be the key residues for the telomerase activity.

  20. Clinical status of anti-cancer agents derived from marine sources.

    Science.gov (United States)

    Singh, Ram; Sharma, Mukul; Joshi, Penny; Rawat, Diwan S

    2008-08-01

    The chemical, biological and ecological diversity of the marine ecosystem has contributed immensely in the discovery of extremely potent compounds that have shown potent activities in antitumor, analgesia, antiinflammatory, immunomodulation, allergy, anti-viral etc. The compounds of marine origin are diverse in structural class from simple linear peptides to complex macrocyclic polyethers. The recent advances in the sophisticated instruments for the isolation and characterization of marine natural products and development of high-throughput screening, have substantially increased the rate of discovery of various compounds of biomedical application. Didemnin was the first marine peptide that entered in human clinical trials in US for the treatment of cancer and other compounds such as dolastatin-10, soblidotin, didemnin B, ecteinascidin 743, girolline, aplidine, cryptophycins (also arenastatin A), bryostatin 1, ILX 651, kahalalide F, E7389, discodermolide, ES-285 (spisulosine), HTI-286 (hemiasterlin derivative), squalamine, KRN-7000, vitilevuamide, Laulimalide, Curacin A, diazonamide, peloruside A, eleutherobin, sarcodictyin, thiocoraline, salicylihalimides A, ascididemnin, CGX-1160, CGX-1007dictyodendrins, GTS-21 (aka DMBX), manoalide, IPL-576,092 (aka HMR-4011A) have entered in the clinical trials. This article summarize clinical status and synthetic advances of some of these compounds.

  1. 1,3-Oxazole derivatives as potential anticancer agents: Computer modeling and experimental study.

    Science.gov (United States)

    Semenyuta, Ivan; Kovalishyn, Vasyl; Tanchuk, Vsevolod; Pilyo, Stepan; Zyabrev, Vladimir; Blagodatnyy, Volodymyr; Trokhimenko, Olena; Brovarets, Volodymyr; Metelytsia, Larysa

    2016-12-01

    Microtubules play a significant role in cell growth and functioning. Therefore inhibition of the microtubule assemblies has emerged as one of the most promising cancer treatment strategies. Predictive QSAR models were built on a series of selective inhibitors of the tubulin were performed by using Associative Neural Networks (ANN). To overcome the problem of data overfitting due to the descriptor selection, a 5-fold cross-validation with variable selection in each step of the analysis was used. All developed QSAR models showed excellent statistics on the training (total accuracy: 0.96-0.97) and test sets (total accuracy: 0.95-97). The models were further validated by 11 synthesized 1,3-oxazole derivatives and all of them showed inhibitory effect on the Hep-2 cancer cell line. The most promising compound showed inhibitory activity IC50=60.2μM. In order to hypothesize their mechanism of action the top three compounds were docked in the colchicine binding site of tubulin and showed reasonable docking scores as well as favorable interactions with the protein.

  2. Discovery of indeno[1,2-b]quinoxaline derivatives as potential anticancer agents.

    Science.gov (United States)

    Tseng, Chih-Hua; Chen, You-Ren; Tzeng, Cherng-Chyi; Liu, Wangta; Chou, Chon-Kit; Chiu, Chien-Chih; Chen, Yeh-Long

    2016-01-27

    We have synthesized certain indeno[1,2-b]quinoxaline derivatives for antiproliferative evaluation. Among them, 11-{[3-(dimethylamino)propoxy]imino}-N-[3-(dimethylamino) propyl]-11H-indeno[1,2-b]quinoxaline-6-carboxamide (10a) was active against the growth of MDA-MB231, PC-3, and Huh-7 with IC50 values of 0.87 (selectivity index, SI = 36.22), 0.82 (SI = 38.43), and 0.64 μM (SI = 49.23) respectively. Compound 10a was inactive against the growth of normal human fetal lung fibroblast cell line (MRC-5) with an IC50 value of 31.51 μM. Its analogs, 10b and 10c, were also active against the growth of MB231, PC-3, and Huh-7 with IC50 values of <1.0 μM in each case. Our results have also indicated compounds 10a-10c exhibited comparable inhibitory activities against topo I and topo II with the positive compound 2 at a concentration of 10 μM. Mechanism studies indicated that compound 10a induced cell cycle arrest at S phase via activation of caspase-3, -7 and an increase in the protein expression of Bad and Bax but a decrease in expression of Bcl-2 and PARP, which consequently cause cell death. In addition, compound 10a attenuated the levels of phosphorylated Src, Akt-1, and Akt-2 protein levels but did not affect the total protein expression of Akt. We have also implanted human hepatocellular carcinoma cells into the yolk sac of zebrafish larvae and incubated larvae with various concentrations of 10a. Our results of the zebrafish xenograft assay confirmed the anti-tumor effect of 10ain vivo.

  3. The Pseudomonas Quinolone Signal (PQS)

    DEFF Research Database (Denmark)

    Sams, Thomas; Baker, Ysobel; Hodgkinson, James;

    2015-01-01

    is now known to be under the con-trol of the quorum sensing (QS) system. Over the last15 years, the Pseudomonas quinolone signal (PQS) has beenfound to play a crucial role in QS by linking the two seg-ments (las and rhl) of the P. aeruginosa N-acylhomoserinelactone-dependent QS signaling pathways. Herein...

  4. A "Double-Edged" Scaffold: Antitumor Power within the Antibacterial Quinolone.

    Science.gov (United States)

    Bisacchi, Gregory S; Hale, Michael R

    2016-01-01

    In the late 1980s, reports emerged describing experimental antibacterial quinolones having significant potency against eukaryotic Type II topoisomerases (topo II) and showing cytotoxic activity against tumor cell lines. As a result, several pharmaceutical companies initiated quinolone anticancer programs to explore the potential of this class in comparison to conventional human topo II inhibiting antitumor drugs such as doxorubicin and etoposide. In this review, we present a modern re-evaluation of the anticancer potential of the quinolone class in the context of today's predominantly pathway-based (rather than cytotoxicity-based) oncology drug R&D environment. The quinolone eukaryotic SAR is comprehensively discussed, contrasted with the corresponding prokaryotic data, and merged with recent structural biology information which is now beginning to help explain the basis for that SAR. Quinolone topo II inhibitors appear to be much less susceptible to efflux-mediated resistance, a current limitation of therapy with conventional agents. Recent advances in the biological understanding of human topo II isoforms suggest that significant progress might now be made in overcoming two other treatment-limiting disadvantages of conventional topo II inhibitors, namely cardiotoxicity and drug-induced secondary leukemias. We propose that quinolone class topo II inhibitors could have a useful future therapeutic role due to the continued need for effective topo II drugs in many cancer treatment settings, and due to the recent biological and structural advances which can now provide, for the first time, specific guidance for the design of a new class of inhibitors potentially superior to existing agents.

  5. [The molecular physiological and genetic mechanisms underlying the superb efficacy of quinolones].

    Science.gov (United States)

    Long, Quan-xin; He, Ying; Xie, Jian-ping

    2012-08-01

    The fluoroquinolones are the most widely used broad-spectrum antibiotics, accounting for 18% of global antibacterial market share. They can kill bacteria rapidly with variety of derivatives available. Different quinolones vary significantly in rate and spectrum of killing, oxygen requirement for metabolism and reliance upon protein synthesis. Further understanding the sophisticated mechanisms of action of this important antibiotic family based on the molecular genetic response of bacteria can facilitate the discovery of better quinolone derivatives. Factors such as SOS response, bacterial toxin-antitoxin system, programmed death, chromosome fragmentation and reactive oxygen have been implicated in the action to some extent. "Two steps characteristic" of quinolones killing is also emphasized, which might inspire future better quinolones modification.

  6. Quinolone resistance: much more than predicted

    Directory of Open Access Journals (Sweden)

    Alvaro eHernandez

    2011-02-01

    Full Text Available Since quinolones are synthetic antibiotics, it was predicted that mutations in target genes would be the only mechanism through which resistance could be acquired, because there will not be quinolone resistance genes in nature. Contrary to this prediction, a variety of elements ranging from efflux pumps, target-protecting proteins and even quinolone-modifying enzymes have been shown to contribute to quinolone resistance. The finding of some of these elements in plasmids indicates that quinolone resistance can be transferable. As a result, there has been a developing interest on the reservoirs for quinolone resistance genes and on the potential risks associated with the use of these antibiotics in non-clinical environments. As a matter of fact, plasmid-encoded, quinolone-resistance qnr genes originated in the chromosome of aquatic bacteria, thus the use of quinolones in fish farming might constitute a risk for the emergence of resistance. Failure to predict the development of quinolone resistance reinforces the need of taking into consideration the wide plasticity of biological systems for future predictions. This plasticity allows pathogens to deal with toxic compounds, including those with a synthetic origin as quinolones.

  7. Anticancer efficacy of a nitric oxide-modified derivative of bifendate against multidrug-resistant cancer cells.

    Science.gov (United States)

    Ren, Zhiguang; Gu, Xiaoke; Lu, Bin; Chen, Yaqiong; Chen, Guojiang; Feng, Jiannan; Lin, Jizhen; Zhang, Yihua; Peng, Hui

    2016-06-01

    The development of multidrug resistance (MDR) not only actively transports a wide range of cytotoxic drugs across drug transporters but is also a complex interaction between a number of important cellular signalling pathways. Nitric oxide donors appear to be a new class of anticancer therapeutics for satisfying all the above conditions. Previously, we reported furoxan-based nitric oxide-releasing compounds that exhibited selective antitumour activity in vitro and in vivo. Herein, we demonstrate that bifendate (DDB)-nitric oxide, a synthetic furoxan-based nitric oxide-releasing derivative of bifendate, effectively inhibits the both sensitive and MDR tumour cell viability at a comparatively low concentration. Interestingly, the potency of DDB-nitric oxide is the independent of inhibition of the functions and expressions of three major ABC transporters. The mechanism of DDB-nitric oxide appears to be in two modes of actions by inducing mitochondrial tyrosine nitration and apoptosis, as well as by down-regulating HIF-1α expression and protein kinase B (AKT), extracellular signal-regulated kinases (ERK), nuclear factor κB (NF-κB) activation in MDR cells. Moreover, the addition of a typical nitric oxide scavenger significantly attenuated all the effects of DDB-nitric oxide, indicating that the cytotoxicity of DDB-nitric oxide is as a result of higher levels of nitric oxide release in MDR cancer cells. Given that acquired MDR to nitric oxide donors is reportedly difficult to achieve and genetically unstable, compound like DDB-nitric oxide may be a new type of therapeutic agent for the treatment of MDR tumours.

  8. Thermodynamic study by infrared spectroscopy of the association of 2-quinolone, some carboxylic acids, and the corresponding 2-quinolone--acid mixed dimers

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, J.C.

    1971-01-01

    Self-association of 2-quinolone in carbon tetrachloride was studied by infrared spectroscopy, using the absorption bands in the amide NH and carbonyl stretching regions. 2-Quinolone forms a cyclic dimer from which the enthalpy (..delta..H/sup 0/, kcal/mol), free energy (..delta..G/sup 0//sub 22/, kcal/mol), and entropy (..delta..S/sup 0/, eu) of association are -8.69, -6.11, and -8.76, respectively. Dimer formation is via a carbonyl-hydrogen bond, although evidence exists for the formation of a small amount of dimer via a ..pi..-hydrogen bond. 2-Quinolone was also found to form cyclic mixed dimers with carboxylic acids. Mixed dimers of 2-quinolone with benzoic, cyclohexanecarboxylic, and 4-cyclohexylbutanoic acids gave ..delta..H/sup 0/ values of -12.2, -10.3, and -10.4; ..delta..G/sup 0//sub 22/ values of -6.36, -5.94, and -5.78; and ..delta..S/sup 0/ values of -19.9, -14.8, and -15.6, respectively. Thermodynamic data on the acid dimers and spectral data on the different systems studied are also reported. The 2-quinolone-carboxylic acid interaction is of importance because of the simultaneous occurrence of quinolones and carboxylic acids in many biologically derived materials.

  9. NCI in vitro and in silico anticancer screen, cell cycle pertubation and apoptosis-inducing potential of new acylated, benzylidene and isopropylidene derivatives of andrographolide.

    Science.gov (United States)

    Wong, Charng Choon; Sagineedu, Sreenivasa Rao; Sumon, Shariful Hasan; Sidik, Shiran Mohamad; Phillips, Roger; Lajis, Nordin H; Stanslas, Johnson

    2014-09-01

    Andrographolide (AGP) is the main bioactive constituent isolated from the traditional medicinal, Andrographis paniculata which contributes towards its various biological activities, including anticancer property. In this study, a series of new AGP derivatives were semi-synthesised and screened against the NCI in vitro 60 cell lines. From the screening results, we had identified SRS07 as the most potent AGP derivative, against breast and colon cancer cell lines. Subsequently, SRS07 was tested for its capability to induce cell cycle arrest and apoptosis in MCF-7 and HCT116 cancer cells. SRS07 effectively induced G1 cell cycle arrest in both cell lines and ultimately apoptosis by inducing DNA fragmentation in HCT116 cells. The apoptotic cell death induced by SRS07 was confirmed via FITC Annexin-V double staining. Western blot analysis of SRS07-treated HCT116 cells revealed that the compound induced apoptosis be activating caspase 8 which in turn cleaved Bid to t-Bid to initiate cell death cascade. Prediction of the possible mode of action of SRS07 by utilising NCI COMPARE analysis failed to reveal a distinct mechanism category. Hence, it is speculated that SRS07 possesses novel mechanism of action. In conclusion, SRS07 demonstrated superior in vitro anticancer profiles and emerged as a potential lead anticancer candidate.

  10. Antitumor Activity of Artemisinin and Its Derivatives: From a Well-Known Antimalarial Agent to a Potential Anticancer Drug

    Directory of Open Access Journals (Sweden)

    Maria P. Crespo-Ortiz

    2012-01-01

    Full Text Available Improvement of quality of life and survival of cancer patients will be greatly enhanced by the development of highly effective drugs to selectively kill malignant cells. Artemisinin and its analogs are naturally occurring antimalarials which have shown potent anticancer activity. In primary cancer cultures and cell lines, their antitumor actions were by inhibiting cancer proliferation, metastasis, and angiogenesis. In xenograft models, exposure to artemisinins substantially reduces tumor volume and progression. However, the rationale for the use of artemisinins in anticancer therapy must be addressed by a greater understanding of the underlying mechanisms involved in their cytotoxic effects. The primary targets for artemisinin and the chemical base for its preferential effects on heterologous tumor cells need yet to be elucidated. The aim of this paper is to provide an overview of the recent advances and new development of this class of drugs as potential anticancer agents.

  11. Design and synthesis of novel tetrahydro-2H-Pyrano[3,2-c]pyridazin-3(6H)-one derivatives as potential anticancer agents.

    Science.gov (United States)

    Al-Tel, Taleb H

    2010-12-01

    Polyfunctional tetrahydro-2H-pyrano[3,2-c]pyridazin-3(6H)-one derivatives were synthesized and biologically evaluated as novel anticancer agents. These motifs were produced by a five-step reaction sequence in which the Achmatowicz oxidative cyclization, is the basic core for such synthesis. Compounds 15f, 16c, and 16d showed antiproliferative activity against the SK-BR-3 breast cancer cell line. Importantly, 16c and 16d showed the highest efficacy, being approximately 30-fold more potent against SK-BR-3 (IC50 0.21 and 0.15 μM, respectively) compared to other cancer cell lines tested. In addition, 16c and 16d displayed about 295 fold less toxicity against normal breast cell line MCF10A compared to SK-BR-3 breast cancer cells. These compounds form the foundation for further investigation in our continuing efforts to develop potent anticancer agents.

  12. Mechanism of quinolone action and resistance.

    Science.gov (United States)

    Aldred, Katie J; Kerns, Robert J; Osheroff, Neil

    2014-03-18

    Quinolones are one of the most commonly prescribed classes of antibacterials in the world and are used to treat a variety of bacterial infections in humans. Because of the wide use (and overuse) of these drugs, the number of quinolone-resistant bacterial strains has been growing steadily since the 1990s. As is the case with other antibacterial agents, the rise in quinolone resistance threatens the clinical utility of this important drug class. Quinolones act by converting their targets, gyrase and topoisomerase IV, into toxic enzymes that fragment the bacterial chromosome. This review describes the development of the quinolones as antibacterials, the structure and function of gyrase and topoisomerase IV, and the mechanistic basis for quinolone action against their enzyme targets. It will then discuss the following three mechanisms that decrease the sensitivity of bacterial cells to quinolones. Target-mediated resistance is the most common and clinically significant form of resistance. It is caused by specific mutations in gyrase and topoisomerase IV that weaken interactions between quinolones and these enzymes. Plasmid-mediated resistance results from extrachromosomal elements that encode proteins that disrupt quinolone-enzyme interactions, alter drug metabolism, or increase quinolone efflux. Chromosome-mediated resistance results from the underexpression of porins or the overexpression of cellular efflux pumps, both of which decrease cellular concentrations of quinolones. Finally, this review will discuss recent advancements in our understanding of how quinolones interact with gyrase and topoisomerase IV and how mutations in these enzymes cause resistance. These last findings suggest approaches to designing new drugs that display improved activity against resistant strains.

  13. Insight into Prodrugs of Quinolones and Fluoroquinolones.

    Science.gov (United States)

    Sharma, Prabodh Chander; Piplani, Mona; Mittal, Monika; Pahwa, Rakesh

    2016-01-01

    Quinolones and fluoroquinolones are principal weapons against variety of bacterial infections and exert their antibacterial potential by interfering the activities of bacterial enzymes. As these agents are associated with some limitations, an important approach to overcome these major constraints is to prepare covalent derivatives, i.e. prodrugs. Prodrug design has been employed to improve the limitations of these drugs such as less aqueous solubility, poor absorption and distribution, toxicity, disagreeable taste, poor lipophilicity etc and for improving their pharmacological profile. This paper highlights the utility of various prodrug strategies in optimizing the therapeutic index of these antibacterial agents and their recent patents. Some of their prodrugs being utilized at preclinical and clinical levels have also been discussed. Hence, this paper has been prepared to present the significant findings of various research papers that would be helpful in motivating scientific researchers to forward the research in direction of utilization of prodrugs in clinical therapy.

  14. In vitro activity of Ozenoxacin against quinolone-susceptible and quinolone-resistant gram-positive bacteria.

    Science.gov (United States)

    López, Y; Tato, M; Espinal, P; Garcia-Alonso, F; Gargallo-Viola, D; Cantón, R; Vila, J

    2013-12-01

    In vitro activity of ozenoxacin, a novel nonfluorinated topical (L. D. Saravolatz and J. Leggett, Clin. Infect. Dis. 37:1210-1215, 2003) quinolone, was compared with the activities of other quinolones against well-characterized quinolone-susceptible and quinolone-resistant Gram-positive bacteria. Ozenoxacin was 3-fold to 321-fold more active than other quinolones. Ozenoxacin could represent a first-in-class nonfluorinated quinolone for the topical treatment of a broad range of dermatological infections.

  15. Molecular structure and spectroscopic investigations combined with hypoglycemic/anticancer and docking studies of a new barbituric acid derivative

    Science.gov (United States)

    Barakat, Assem; Soliman, Saied M.; Elshaier, Yaseen A. M. M.; Ali, M.; Al-Majid, Abdullah Mohammed; Ghabbour, Hazem A.

    2017-04-01

    The one-pot synthesis reaction of barbituric acid derivative, 1,3-cyclohexandione, and 4-fluorobenzaldehyde in water mediated by NHEt2 as base afforded 4 with excellent yield. The synthesized compound was characterized by spectrophotometric tools as well as X-ray single crystal diffraction technique. The stability of the nine possible isomers of the synthesized compound was studied using the B3LYP method and 6-31G(d,p) basis set. The electronic and spectroscopic properties of the most stable isomer were predicted. The UV-Vis absorption spectrum displayed two bands at 203 and 257 nm in the solvent chloroform. The latter was calculated at 235.6 nm (f = 0.1995) in the gas phase due to H-2→L (42%) and H-1→L+2 (14%) excitations. In solution, using chloroform as a solvent, a slight bathochromic shift to 237.6 nm with an increase in the absorption intensity (f = 0.2898) was predicted. The molecular orbital energy level diagram of this transition band was characterized mainly by π-π* transitions. The 13C and 1H NMR chemical shifts correlated well with the experimental data. The correlations had higher correlation coefficients (R2) when solvent effects were considered. The atomic charges were calculated using natural population analysis and the charged regions were presented using a molecular electrostatic potential (MEP) map. The synthesized compound was examined as a hypoglycemic agent via inhibition of α-glucosidase and β-glucuronidase enzymes. Its inhibitory activity against α-glucosidase was 10 times greater than the inhibitory activity of the standard drug acarbose (IC50 77.9 ± 0.3 μM and 840 ± 1.73 μM, respectively). Moreover, the target compound was evaluated for anticancer activity against MCF-7, H460, 3T3, and Hela cell lines. It demonstrated inhibitory activity against the MCF-7 and H460 cell lines with IC50 5.80 ± 0.12 and 19.6 ± 0.5 μM, respectively, in comparison to doxorubicin. The docking study was performed using the OpenEye program.

  16. Transport characteristics of L-carnosine and the anticancer derivative 4-toluenesulfonylureido-carnosine in a human epithelial cell line

    DEFF Research Database (Denmark)

    Nielsen, Carsten Uhd; Supuran, Claudiu T; Scozzafava, Andrea;

    2002-01-01

    The aim of the present study was to evaluate whether the transepithelial transport of the anticancer compound 4-toluenesulfonylureido-carnosine (Ts-carnosine) and the dipeptide moiety L-carnosine was due to a hPepT1 carrier-mediated flux....

  17. Discovery of Quinoline-Derived Trifluoromethyl Alcohols, Determination of Their in vivo Toxicity and Anticancer Activity in a Zebrafish Embryo Model.

    Science.gov (United States)

    Sittaramane, Vinoth; Padgett, Jihan; Salter, Philip; Williams, Ashley; Luke, Shauntelle; McCall, Rebecca; Arambula, Jonathan F; Graves, Vincent B; Blocker, Mark; Van Leuven, David; Bowe, Keturah; Heimberger, Julia; Cade, Hannah C; Immaneni, Supriya; Shaikh, Abid

    2015-11-01

    In this study the rational design, synthesis, and anticancer activity of quinoline-derived trifluoromethyl alcohols were evaluated. Members of this novel class of trifluoromethyl alcohols were identified as potent growth inhibitors in a zebrafish embryo model. Synthesis of these compounds was carried out with an sp(3) -C-H functionalization strategy of methyl quinolines with trifluoromethyl ketones. A zebrafish embryo model was also used to explore the toxicity of ethyl 4,4,4-trifluoro-3-hydroxy-3-(quinolin-2-ylmethyl)butanoate (1), 2-benzyl-1,1,1-trifluoro-3-(quinolin-2-yl)propan-2-ol (2), and trifluoro-3-(isoquinolin-1-yl)-2-(thiophen-2-yl)propan-2-ol (3). Compounds 2 and 3 were found to be more toxic than compound 1; apoptotic staining assays indicated that compound 3 causes increased cell death. In vitro cell proliferation assays showed that compound 2, with an LC50 value of 14.14 μm, has more potent anticancer activity than cisplatin. This novel class of inhibitors provides a new direction in the discovery of effective anticancer agents.

  18. DRUG-INTERACTIONS WITH QUINOLONE ANTIBACTERIALS

    NARCIS (Netherlands)

    BROUWERS, JRBJ

    1992-01-01

    The quinolone antibacterials are prone to many interactions with other drugs. Quinolone absorption is markedly reduced with antacids containing aluminium, magnesium and/or calcium and therapeutic failure may result. Other metallic ion-containing drugs, such as sucralfate, iron salts, and zinc salts,

  19. [Quinolones. Nowadays perspectives and mechanisms of resistance].

    Science.gov (United States)

    Álvarez-Hernández, Diego Abelardo; Garza-Mayén, Gilda Sofía; Vázquez-López, Rosalno

    2015-10-01

    Quinolones are a family of synthetic broad-spectrum antimicrobial drugs whose target is the synthesis of DNA. They directly inhibit DNA replication by interacting with two enzymes; DNA gyrase and topoisomerase IV. They have been widely used for the treatment of several community and hospital acquired infections, in the food processing industry and in the agricultural field, making the increasing incidence of quinolone resistance a frequent problem associated with constant exposition to diverse microorganisms. Resistance may be achieved by three non-exclusive mechanisms; through chromosomic mutations in the Quinolone Resistance-Determining Regions of DNA gyrase and topoisomerase IV, by reducing the intracytoplasmic concentrations of quinolones actively or passively and by Plasmid-Mediated Quinolones-Resistance genes, [Qnr determinant genes of resistance to quinolones, variant gene of the aminoglycoside acetyltransferase (AAC(6')-Ib-c)] and encoding genes of efflux pumps (qepA and oqxAB)]. The future of quinolones is uncertain, however, meanwhile they continue to be used in an irrational way, increasing resistance to quinolones should remain as an area of primary priority for research.

  20. Anti-cancer agents based on 4-(hetero)Ary1-1,2,5-oxadiazol-3-yl Amino derivatives and a method of making

    Science.gov (United States)

    Gakh, Andrei A.; Krasavin, Mikhail; Karapetian, Ruben; Rufanov, Konstantin A.; Konstantinov, Igor; Godovykh, Elena; Soldatkina, Olga; Sosnov, Andrey V.

    2013-01-29

    The present disclosure relates to novel compounds that can be used as anti-cancer agents in the prostate cancer therapy. ##STR00001## In particular, the invention relates N-substituted derivatives of 4-(hetero)aryl-1,2,5-oxadiazol-3-yl amines having the structural Formula (I) and (II), stereoisomers, tautomers, racemics, prodrugs, metabolites thereof, or pharmaceutically acceptable salt and/or solvate thereof. Meaning of R1 and R2 in the Formula (I) and (II) are defined in claim 1. The invention also relates to methods for preparing said compounds, and to pharmaceutical compositions comprising said compounds.

  1. Design, synthesis, anticancer, antimicrobial activities and molecular docking studies of theophylline containing acetylenes and theophylline containing 1,2,3-triazoles with variant nucleoside derivatives.

    Science.gov (United States)

    Ruddarraju, Radhakrishnam Raju; Murugulla, Adharvana Chari; Kotla, Ravindar; Chandra Babu Tirumalasetty, Muni; Wudayagiri, Rajendra; Donthabakthuni, Shobha; Maroju, Ravichandar; Baburao, K; Parasa, Lakshmana Swamy

    2016-11-10

    A new series of theophylline containing acetylene derivatives (6a-6b and 7-13) and theophylline containing 1,2,3-triazoles with variant nucleoside derivatives (20-32) have been designed and synthesized. These compounds were screened for anticancer and antimicrobial activity. Further the computational docking and 2D QSAR were performed using MOE software to identify novel scaffolds. The results showed that compound 29 and 30 exhibit significant cytotoxic effect on all four cancer cells such as lung (A549), colon (HT-29), breast (MCF-7) and melanoma (A375) with IC50 values of 2.56, 2.19, 1.89, 4.89 μM and 3.57, 2.90, 2.10, 5.81 μM respectively. Whereas quite different results were observed for these compounds in antimicrobial studies. Compounds 11, 21 and 26 have exhibited significant minimum inhibitory concentrations (MIC) against Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa. The docking studies demonstrate that compound 27, 28, 29 and 30 have good dock score and binding affinities with various therapeutic targets in cancer cell proliferation. In addition these compounds have shown acceptable correlation with bioassay results in the regression plots generated in 2D QSAR models. This is the first report to demonstrate the theophylline containing acetylene derivatives and theophylline containing 1,2,3-triazole nucleoside hybrids as potential anticancer and antimicrobial agents with comprehensive in silico analysis.

  2. Molecular approaches towards development of purified natural products and their structurally known derivatives as efficient anti-cancer drugs: current trends.

    Science.gov (United States)

    Saha, Santu Kumar; Khuda-Bukhsh, Anisur Rahman

    2013-08-15

    Several natural products and their derivatives, either in purified or structurally identified form, exhibit immense pharmacological and biological properties, some of them showing considerable anticancer potential. Although the molecular mechanisms of action of some of these products are yet to be elucidated, extensive research in this area continues to generate new data that are clinically exploitable. Recent advancement in molecular biology, high throughput screening, biomarker identifications, target selection and genomic approaches have enabled us to understand salient interactions of natural products and their derivatives with cancer cells vis-à-vis normal cells. In this review we highlight the recent approaches and application of innovative technologies made to improve quality as well as efficiency of structurally identified natural products and their derivatives, particularly in small molecular forms capable of being used in "targeted therapies" in oncology. These products preferentially involve multiple mechanistic pathways and overcome chemo-resistance in tumor types with cumulative action. We also mention briefly a few physico-chemical features that compare natural products with drugs in recent natural product discovery approaches. We further report here a few purified natural products as examples that provide molecular interventions in cancer therapeutics to give the reader a glimpse of the current trends of approach for discovering useful anticancer drugs.

  3. Synthesis, biological evaluation and molecular docking studies of some novel cyclopropane carbohydrazide derivatives as potential anticancer agents

    Indian Academy of Sciences (India)

    PONNAPALLI VEERABHADRA SWAMY; PULLAIAH CHINA KAMBHAMPATI; KOTHAPALLI BONNOTH CHANDRASEKHAR; GUGULOTHU THIRUPATHI; POMBALA SUJITHA; CHITYAL GANESH KUMAR; VEERAMACHANENI GANESH KUMAR

    2016-06-01

    The synthesis of novel series of cyclopropane carbohydrazides is described via Knoevenagel condensationof 2-furfuraldehyde with malonic acid in five steps. Condensation of the key intermediate 2-(furan-2-yl)cyclopropanecarbohydrazide (4) with heteroaryl/aryl aldehydes (a-t) in presence of ZnO NP in ethanolresulted in substituted N- hetero/arylidene-2-(furan-2-yl) cyclopropane carbohydrazides (5a-t). These compoundswere screened for their anticancer activity against a panel of four cancer cell lines and four compoundsshowed promising activity at micromolar concentration against all the tested cell lines with IC50 values rangingbetween 1.9-8.45μM. These compounds were further validated with in silico methods at the anticancer target,colchicine binding site.

  4. [Review and categorization of quinolone antibiotics].

    Science.gov (United States)

    Benes, Jirí

    2005-02-01

    No standard categorization of quinolone antibiotics into generations may be found in either Czech or world literature. The author recommends a categorization into four groups defined according to their spectrum of action and utilization: 1) preparations for the treatment of urinary tract infections; 2) systemically acting quinolones chiefly efficacious against Gram-negative bacteria; 3) so-called respiratory quinolones; and 4) quinolones with a very broad spectrum of action suitable for the treatment of very complicated infections. The author describes the chief characteristics of the most important quinolone antibiotics, including preparations either in their development stage or whose development has been prematurely interrupted because of adverse side-effects. The list includes all preparations that are or were temporarily registered in the Czech Republic.

  5. 4-Quinolone-3-carboxylic acids as cell-permeable inhibitors of protein tyrosine phosphatase 1B.

    Science.gov (United States)

    Zhi, Ying; Gao, Li-Xin; Jin, Yi; Tang, Chun-Lan; Li, Jing-Ya; Li, Jia; Long, Ya-Qiu

    2014-07-15

    Protein tyrosine phosphatase 1B is a negative regulator in the insulin and leptin signaling pathways, and has emerged as an attractive target for the treatment of type 2 diabetes and obesity. However, the essential pharmacophore of charged phosphotyrosine or its mimetic confer low selectivity and poor cell permeability. Starting from our previously reported aryl diketoacid-based PTP1B inhibitors, a drug-like scaffold of 4-quinolone-3-carboxylic acid was introduced for the first time as a novel surrogate of phosphotyrosine. An optimal combination of hydrophobic groups installed at C-6, N-1 and C-3 positions of the quinolone motif afforded potent PTP1B inhibitors with low micromolar IC50 values. These 4-quinolone-3-carboxylate based PTP1B inhibitors displayed a 2-10 fold selectivity over a panel of PTP's. Furthermore, the bidentate inhibitors of 4-quinolone-3-carboxylic acids conjugated with aryl diketoacid or salicylic acid were cell permeable and enhanced insulin signaling in CHO/hIR cells. The kinetic studies and molecular modeling suggest that the 4-quinolone-3-carboxylates act as competitive inhibitors by binding to the PTP1B active site in the WPD loop closed conformation. Taken together, our study shows that the 4-quinolone-3-carboxylic acid derivatives exhibit improved pharmacological properties over previously described PTB1B inhibitors and warrant further preclinical studies.

  6. Evaluation of quinolone antibacterial consumption

    Directory of Open Access Journals (Sweden)

    E. P. Bernaz

    2016-08-01

    Full Text Available Quinolones are broad-spectrum antibiotics that play an important role in the treatment of serious bacterial infections, especially hospital-acquired infections and others in which resistance to older antibacterial classes is suspected and as first-line therapy is recommended. To determine the place, compare and analyze the use of quinolone antibacterial in the most important departments of EMI during 2009 to 2014 and to assess their results for improvement of patients treatment quality was designed this study. In the evaluated period consumption of quinolone antibacterial in EMI recorded a decline from 91 to 46 DDD/1000 or by 49.45%, in IC departaments from 338.6 to 132.07 or by 61%, and vice versa in SSOT departments an increase from 41.28 to 57.59 DDD/1000 or by 31.51%. Medium annual consumption in all institution recorded 63.03 DDD/1000, respectvely 174.90 in IC and 45.10 in SSOT departments. In 2014 IC departments recorded 2439.8 lei per DDD/1000, that was 8.72 times more than cost of 279.9 lei in SSOT departments and 7.51 times than 324.96 lei per DDD/1000 in all EMI. The yearly medium in EMI is around the same with all other international hospitals of 66.13 DDD/1000 and by 27.23% higher than 49.54 DDD/1000 recorded in large acute Australian public hospitals. The obtained results will be an important data for optimization in planning annual hospital necessities and rational antimicrobial prescribing as well as suggest the idea for expansion development and support antimicrobial stewardship initiatives.

  7. Design, synthesis and anticancer activity of new 3-cyano-2 (1H -pyridone and 3-cyanopyridine-2-(1H-thione derivatives

    Directory of Open Access Journals (Sweden)

    E. A. Abdel Motaal

    2015-06-01

    Full Text Available The main objective of the present research study is to synthesize some novel chalcone, cyanoacetohydrazone, enaminone, 3-cyano-2(1H-pyridone and 3-cyanopyridine-2-(1H-thione derivatives and evaluate them for their anticancer effect. The novel chalcones 2a-c were achieved by Claisen-Schmidt condensation of appropriate benzaldehydes with ethanone derivative 1. Treatment of cyanoacetic acid hydrazide with ethanone derivative 1 yielded the correspondinghydrazone derivative 3. Condensation of ethanone derivative 1 with DMF-DMA afforded (E-3-(dimethylamino-1- (4- morpholinophenylprop-2-en-1-one 4. Heterocyclization of chalcones 2a-c with cyanothioacetamide yielded 2-thioxo-1,2-dihydropyridine-3-carbonitriles 7a-c. In a similar manner, cyclocondensation of chalcones 2a,b with cyanoacetamide afforded the corresponding 2-oxo-1,2-dihydropyridine-3-carbonitriles 8a,b. The Reaction of compound 2a with ethyl cyanoacetate furnished 2-oxo-1,2-dihydropyridine-3-carboxylate 12. The 2-oxo-4-phenyl-1,2-dihydro-pyridine-3,5-dicarbonitriles 14a,b were obtained by cyclization of cyano-acetohydrazone 3 with cinnamonitriles. The structures of the synthesized compounds were confirmed by elemental analysis, mass spectrometry, IR and 1H-NMR spectroscopy. The anticancer activity of the newly synthesized compounds was screened in vitro against Human lung carcinoma (A 549 cell line indicating that compounds 7b and 8a possess the most potent inhibitory effect against the human lung carcinoma cell line (A549.

  8. Synthesis and anticancer activity evaluation of new 2-alkylcarbonyl and 2-benzoyl-3-trifluoromethyl-quinoxaline 1,4-di-N-oxide derivatives.

    Science.gov (United States)

    Zarranz, Belén; Jaso, Andrés; Aldana, Ignacio; Monge, Antonio

    2004-07-01

    As a continuation of our research in quinoxaline 1,4-di-N-oxide and with the aim of obtaining new anticancer agents, which can improve the current chemotherapeutic treatments, new series of 2-alkylcarbonyl and 2-benzoyl-3-trifluoromethylquinoxaline 1,4-di-N-oxide derivatives have been synthesized and evaluated for in vitro antitumor activity against a 3-cell line panel, consisting of MCF7 (breast), NCI-H460 (lung), and SF-268 (CNS). These active compounds were then evaluated in the full panel of 60 human tumor cell lines derived from nine cancer cell types. The results have shown that, in general, anticancer activity depends on the substituents in the carbonyl group, improving in the order: ethyl

  9. Synthesis, quantitative structure-activity relationship and biological evaluation of 1,3,4-oxadiazole derivatives possessing diphenylamine moiety as potential anticancer agents.

    Science.gov (United States)

    Abdel Rahman, Doaa Ezzat

    2013-01-01

    Synthesis of 2,5-disubstituted-1,3,4-oxadiazole (2a-c), 3-substituted aminomethyl-5-substituted-1,3,4-oxadiazole-2(3H)-thione (4a-m) and 2-substituted thio-5-substituted-1,3,4-oxadiazole (5a, b) had been described. All the synthesized derivatives were screened for anticancer activity against HT29 and MCF7 cancer cell lines using Sulfo-Rodamine B (SRB) standard method. Most of the tested compounds exploited potent antiproliferative activity against HT29 cancer cell line rather than MCF7 cancer cell line. Compounds 2a-c, 4f and 5a exhibited potent cytotoxicity (IC(50) 1.3-2.0 µM) and selectivity against HT29 cancer cell line. Quantitative structure-activity relationship (QSAR) study was applied to find a correlation between the experimental antiproliferative activities of the newly synthesized oxadiazole derivatives with their physicochemical parameter and topological index.

  10. THEORETICAL STUDY OF PODOPHYLLOTOXIN AND QUINOLONE ANALOGUES AS ANTITUMOR DRUGS

    Institute of Scientific and Technical Information of China (English)

    何峰; 戴颖仪; 朱孝峰; 黄爱东; 张翎; 颜少平; 刘宗潮

    2002-01-01

    Objective: To study the active sites of podophyllotoxin derivatives. Methods: Some podophyllotoxin derivatives were analyzed by quantum and mechanics method. Results: Some information was given according to the calculation results about HOMO and LUMO electron density. The C-4 position is the position for effective modification. The B ring and E ring are important active centers. Conclusion: The hole of positive charge in B ring easily combines with an acceptor within the molecular. Some quinolones with similar electronic construction to podophyllotoxin may have antitumor activity.

  11. Design, synthesis, biological evaluation and molecular docking studies of novel benzofuran-pyrazole derivatives as anticancer agents.

    Science.gov (United States)

    Abd El-Karim, Somaia S; Anwar, Manal M; Mohamed, Neama A; Nasr, Tamer; Elseginy, Samia A

    2015-12-01

    This study deals with design and synthesis of novel benzofuran-pyrazole hybrids as anticancer agents. Eight compounds were chosen by National Cancer Institute (NCI), USA to evaluate their in vitro antiproliferative activity at 10(-5)M in full NCI 60 cell panel. The preliminary screening of the tested compounds showed promising broad-spectrum anticancer activity. Compound 4c was further assayed for five dose molar ranges in full NCI 60 cell panel and exhibited remarkable growth inhibitory activity pattern against Leukemia CCRF-CEM, MOLT-4, Lung Cancer HOP-92, Colon Cancer HCC-2998, CNS Cancer SNB-75, Melanoma SK-MEL-2, Ovarian Cancer IGROV1, Renal Cancer 786-0, RXF 393, Breast Cancer HS 578T and T-47D (GI50: 1.00-2.71μM). Moreover, enzyme assays were carried out to investigate the possible antiproliferative mechanism of action of compound 4c. The results revealed that compound 4c has good c-Src inhibitory activity at 10μM. In addition, molecular docking studies showed that 4c could bind to the ATP Src pocket sites. Fulfilling the Lipinskiís rule of five in addition to its ADME profile and the biological results, all strongly suggest that 4c is a promising Src kinase inhibitor.

  12. Conjugation between quinolone-susceptible bacteria can generate mutations in the quinolone resistance-determining region, inducing quinolone resistance.

    Science.gov (United States)

    Pitondo-Silva, André; Martins, Vinicius Vicente; Silva, Carolina Fávero da; Stehling, Eliana Guedes

    2015-02-01

    Quinolones are an important group of antibacterial agents that can inhibit DNA gyrase and topoisomerase IV activity. DNA gyrase is responsible for maintaining bacteria in a negatively supercoiled state, being composed of subunits A and B. Topoisomerase IV is a homologue of DNA gyrase and consists of two subunits codified by the parC and parE genes. Mutations in gyrA and gyrB of DNA gyrase may confer resistance to quinolones, and the majority of resistant strains show mutations between positions 67 and 106 of gyrA, a region denoted the quinolone resistance-determining region (QRDR). The most frequent substitutions occur at positions 83 and 87, but little is known about the mechanisms promoting appearance of mutations in the QRDR. The present study proposes that some mutations in the QRDR could be generated as a result of the natural mechanism of conjugation between bacteria in their natural habitat. This event was observed following conjugation in vitro of two different isolates of quinolone-susceptible Pseudomonas aeruginosa, which transferred plasmids of different molecular weights to a recipient strain of Escherichia coli (HB101), also quinolone-susceptible, generating two different transconjugants that presented mutations in DNA gyrase and acquisition of resistance to all quinolones tested.

  13. Identification and Preclinical Evaluation of SC144, a Novel Pyrroloquinoxaline Derivative with Broad-Spectrum Anticancer Activity.

    Science.gov (United States)

    Grande, Fedora; Aiello, Francesca; Garofalo, Antonio; Neamati, Nouri

    2016-01-01

    Design and discovery of new classes of anticancer agents with unique mechanisms of action is an urgent medical need. During the past several years, a series of salicylhydrazide class of compounds were reported to possess remarkable potency in a large panel of cancer cell lines from different tumor origins. In particular, the optimized lead compound, SC144, was further investigated and selected as a valuable drug candidate endowed with favorable pharmacokinetic and antiproliferative properties in various in vitro and in vivo xenograft models. This lead compound is active in cells resistant to conventional chemotherapies, synergistic with several standard-of-care drugs, and possesses an unique mechanism acting through the inhibition of the gp130-STAT3-survivin axis. Because of this novel mechanism, clinical development of SC144 will provide new therapeutic options for diverse cancers.

  14. Mechanisms of drug resistance: quinolone resistance.

    Science.gov (United States)

    Hooper, David C; Jacoby, George A

    2015-09-01

    Quinolone antimicrobials are synthetic and widely used in clinical medicine. Resistance emerged with clinical use and became common in some bacterial pathogens. Mechanisms of resistance include two categories of mutation and acquisition of resistance-conferring genes. Resistance mutations in one or both of the two drug target enzymes, DNA gyrase and DNA topoisomerase IV, are commonly in a localized domain of the GyrA and ParE subunits of the respective enzymes and reduce drug binding to the enzyme-DNA complex. Other resistance mutations occur in regulatory genes that control the expression of native efflux pumps localized in the bacterial membrane(s). These pumps have broad substrate profiles that include quinolones as well as other antimicrobials, disinfectants, and dyes. Mutations of both types can accumulate with selection pressure and produce highly resistant strains. Resistance genes acquired on plasmids can confer low-level resistance that promotes the selection of mutational high-level resistance. Plasmid-encoded resistance is due to Qnr proteins that protect the target enzymes from quinolone action, one mutant aminoglycoside-modifying enzyme that also modifies certain quinolones, and mobile efflux pumps. Plasmids with these mechanisms often encode additional antimicrobial resistances and can transfer multidrug resistance that includes quinolones. Thus, the bacterial quinolone resistance armamentarium is large.

  15. Progress in Synthesis of 4-Hydroxyquinoline Derivatives%4-羟基喹啉类化合物的合成研究进展

    Institute of Scientific and Technical Information of China (English)

    茆勇军; 何海军

    2014-01-01

    4-羟基喹啉类[4-hydroxyquinolines或4(1H)quinolones]化合物是一类重要的药物合成中间体,在抗疟、抗癌、抗菌、抗病毒、抗糖尿病等领域发挥重要作用。本文综述了4-羟基喹啉类衍生物的合成方法,包括热环合、碱环合和还原环合等。%4-Hydroxyquinoline [or 4(1H)quinolone] derivatives are important intermediates in pharmaceutical synthesis and play significant roles in antimalarial, anticancer, antibacterial, antiviral and antidiabetic. Progress in synthesis of 4-hydroxyquinoline derivatives, including thermal, basic and reductive cyclization methods, are summarized.

  16. Anti-cancer agents based on N-acyl-2, 3-dihydro-1H-pyrrolo[2,3-b] quinoline derivatives and a method of making

    Science.gov (United States)

    Gakh, Andrei; Krasavin, Mikhail; Karapetian, Ruben; Rufanov, Konstantin A; Konstantinov, Igor; Godovykh, Elena; Soldatkina, Olga; Sosnov, Andrey V

    2013-04-16

    The present disclosure relates to novel compounds that can be used as anti-cancer agents in the prostate cancer therapy. In particular, the invention relates to N-acyl derivatives of 2,3-dihydro-1H-pyrrolo[2,3-b]quinolines having the structural Formula (I), ##STR00001## stereoisomers, tautomers, racemics, prodrugs, metabolites thereof, or pharmaceutically acceptable salt and/or solvate thereof. The meaning of R1 is independently selected from H; C1-C6 Alkyl, cyclo-Alkyl or iso-Alkyl substituents; R2 is selected from C1-C6 Alkyl, cyclo-Alkyl or iso-Alkyl; substituted or non-substituted, fused or non-fused to substituted or non-substituted aromatic ring, aryl or heteroaryl groups. The invention also relates to methods for preparing said compounds, and to pharmaceutical compositions comprising said compounds.

  17. In vitro anti-Mycobacterium avium activities of quinolones: predicted active structures and mechanistic considerations.

    Science.gov (United States)

    Klopman, G; Li, J Y; Wang, S; Pearson, A J; Chang, K; Jacobs, M R; Bajaksouzian, S; Ellner, J J

    1994-08-01

    The relationship between the structures of quinolones and their anti-Mycobacterium avium activities has been previously derived by using the Multiple Computer-Automated Structure Evaluation program. A number of substructural constraints required to overcome the resistance of most of the strains have been identified. Nineteen new quinolones which qualify under these substructural requirements were identified by the program and subsequently tested. The results show that the substructural attributes identified by the program produced a successful a priori prediction of the anti-M. avium activities of the new quinolones. All 19 quinolones were found to be active, and 4 of them are as active or better than ciprofloxacin. With these new quinolones, the updated multiple computer-automated structure evaluation program structure-activity relationship analysis has helped to uncover additional information about the nature of the substituents at the C5 and C7 positions needed for optimal inhibitory activity. A possible explanation of drug resistance based on the observation of suicide inactivation of bacterial cytochrome P-450 by the cyclopropylamine moiety has also been proposed and is discussed in this report. Furthermore, we confirm the view that the amount of the uncharged form present in a neutral pH solution plays a crucial role in the drug's penetration ability.

  18. DNA topoisomerases and their poisoning by anticancer and antibacterial drugs.

    Science.gov (United States)

    Pommier, Yves; Leo, Elisabetta; Zhang, HongLiang; Marchand, Christophe

    2010-05-28

    DNA topoisomerases are the targets of important anticancer and antibacterial drugs. Camptothecins and novel noncamptothecins in clinical development (indenoisoquinolines and ARC-111) target eukaryotic type IB topoisomerases (Top1), whereas human type IIA topoisomerases (Top2alpha and Top2beta) are the targets of the widely used anticancer agents etoposide, anthracyclines (doxorubicin, daunorubicin), and mitoxantrone. Bacterial type II topoisomerases (gyrase and Topo IV) are the targets of quinolones and aminocoumarin antibiotics. This review focuses on the molecular and biochemical characteristics of topoisomerases and their inhibitors. We also discuss the common mechanism of action of topoisomerase poisons by interfacial inhibition and trapping of topoisomerase cleavage complexes.

  19. Investigations on the 4-Quinolone-3-carboxylic Acid Motif. 7. Synthesis and Pharmacological Evaluation of 4-Quinolone-3-carboxamides and 4-Hydroxy-2-quinolone-3-carboxamides as High Affinity Cannabinoid Receptor 2 (CB2R) Ligands with Improved Aqueous Solubility.

    Science.gov (United States)

    Mugnaini, Claudia; Brizzi, Antonella; Ligresti, Alessia; Allarà, Marco; Lamponi, Stefania; Vacondio, Federica; Silva, Claudia; Mor, Marco; Di Marzo, Vincenzo; Corelli, Federico

    2016-02-11

    4-Quinolone-3-carboxamide derivatives have long been recognized as potent and selective cannabinoid type-2 receptor (CB2R) ligands. With the aim to improve their physicochemical properties, basically aqueous solubility, two different approaches were followed, entailing the substitution of the alkyl chain with a basic replacement or scaffold modification to 4-hydroxy-2-quinolone structure. According to the first approach, compound 6d was obtained, showing slightly reduced receptor affinity (K(i) = 60 nM) compared to the lead compound 4 (0.8 nM) but greatly enhanced solubility (400-3400 times depending on the pH of the medium). On the other hand, shifting from 4-quinolone to 4-hydroxy-2-quinolone structure enabled the discovery of a novel class of CB2R ligands, such as 7b and 7c, characterized by K(i) 1300. At pH 7.4, compound 7c resulted by 100-fold more soluble than 4.

  20. Synthesis of quinolones by nickel-catalyzed cycloaddition via elimination of nitrile.

    Science.gov (United States)

    Nakai, Kenichiro; Kurahashi, Takuya; Matsubara, Seijiro

    2013-02-15

    Substituted quinolones were efficiently synthesized via the nickel-catalyzed cycloaddition of o-cyanophenylbenzamide derivatives with alkynes. The reaction involves elimination of a nitrile group by cleavage of the two independent aryl-cyano and aryl-carbonyl C-C bonds of the amides.

  1. Synthesis, saccharide-binding and anti-cancer cell proliferation properties of arylboronic acid derivatives of indoquinolines.

    Science.gov (United States)

    Meng, Junxiu; Yu, Shaoqing; Wan, Shengbiao; Ren, Sumei; Jiang, Tao

    2011-11-01

    A facile synthesis of a series of saccharide-binding arylboronic acid derivatives of indoloquinoline was described. The key synthetic steps were polyphosphoric acid-mediated cyclization, chlorinative aromatization, and amidation. Mass spectrometry experiments revealed these synthetic arylboronic acid derivatives of indoquinolines could bind to biologically important carbohydrates (sialic acid, fucose, glucose, and galactose) by forming boronate di-esters in alkaline aqueous solution. Most of the arylboronic acid derivatives of indoquinolines inhibited human breast cancer cell (MDA-231) proliferation at a concentration of 5 μm, whereas the compound 17 exhibited highest percentages (76.74%) of the cancer cell proliferation inhibition.

  2. Evaluating the Potential of Adipose Tissue-Derived MSCs as Anticancer Gene Delivery Vehicles to Bone-Metastasized Prostate Cancer

    Science.gov (United States)

    2012-10-01

    potential of mesenchymal stromal cells in a mouse breast cancer metastasis model. Cytotherapy. 2009;11(3):289-98. PMID:19308770. 5: Zhao M, Sachs PC, Wang...Park H, Lim EH, Lee KW. Exosomes from breast cancer cells can convert adipose tissue-derived mesenchymal stem cells into myofibroblast-like cells. Int J...JH, Shin JW, Lee KW. Exosomes from ovarian cancer cells induce adipose tissue-derived mesenchymal stem cells to acquire the physical and functional

  3. Synthesis and anticancer activity of novel benzimidazole and benzothiazole derivatives against HepG2 liver cancer cells.

    Science.gov (United States)

    Youssef, Amal M; Malki, Ahmed; Badr, Mona H; Elbayaa, Rasha Y; Sultan, Ahmed S

    2012-03-01

    Most of cancer chemotherapeutics and chemopreventives exert their effects by triggering apoptotic cell death. In this study, novel benzimidazole and benzothiazole derivatives have been synthesized to investigate their effects on HepG2 liver cancer cell lines after initial screening study. A dose response curve was constructed and the most active derivatives were further studied for apoptotic analysis. Six active benzimidazole derivatives (8, 9, 10, 12, 13 and 14) significantly induced apoptosis compared to control group. Two compounds 10 and 12 induced apoptosis by arresting cells in G1 phase of cell cycle which is confirmed by increased expression level of p21. The activity of caspase-3 which is well known as one of the key executioners of apoptosis was determined in the presence and absence of the tested derivatives. Our results indicated that compounds 10 and 12 significantly increased caspase-3 activity compared to control group. Moreover, a docked pose of compounds 10 and 12 was obtained bound to caspase-3 active site using Molecular Operating Environment module. This study demonstrated that benzimidazole derivatives 10 and 12 provoke cytotoxicity and induced apoptosis in liver cancer cells HepG2.

  4. A novel experimental platform for investigating cancer growth and anti-cancer therapy in a human tissue microenvironment derived from human embryonic stem cells.

    Science.gov (United States)

    Tzukerman, Maty; Skorecki, Karl L

    2006-01-01

    There is no available experimental system wherein human cancer cells can be grown in the context of a mixed population of normal differentiated human cells for testing biological aspects of cancer cell growth (tumor cell invasion, angiogenesis) or response to anti-cancer therapies. Human embryonic stem cells when implanted into immunocompromised mice develop teratomas containing complex structures, comprising differentiated cell types representing the major germline-derived lineages. We sought to determine whether human cancer cells would grow within such teratomas and display properties associated with malignancy such as invasiveness and recruitment of blood vessels. Ovarian cancer cells (HEY), stably expressing an H2A-GFP fusion protein, which allows tracking of tumor cells, were injected into mature teratomas and developed into tumors. The growth, proliferation capacity, invasion, and induction of blood vessel formation were examined. We propose using the novel experimental platform we have described, consisting of human tumor cells growing within a human cellular microenvironment derived from human embryonic stem cells, to develop a preclinical model for investigating and manipulating the stromal response in tumor cell growth, as an additional tool in cancer research.

  5. Genotoxicity of quinolones: substituents contribution and transformation products QSAR evaluation using 2D and 3D models.

    Science.gov (United States)

    Li, Min; Wei, Dongbin; Zhao, Huimin; Du, Yuguo

    2014-01-01

    The genotoxicity of 21 quinolones antibiotics was determined using SOS/umu assay. Some quinolones exhibited high genotoxicity, and the chemical substituent on quinolone ring significantly affected genotoxicity. To establish the relationship between genotoxicity and substituent, a 2D-QSAR model based on quantum chemical parameters was developed. Calculation suggested that both steric and electrostatic properties were correlated well with genotoxicity. Furthermore, the specific effect on three key active sites (1-, 7- and 8-positions) of quinolone ring was investigated using a 3D-QSAR (comparative molecular field analysis, CoMFA) method. From our modeling, the genotoxicity increased when substituents had: (1) big volume and/or positive charge at 1-position; (2) negative charge at 7-position; and (3) small volume and/or negative charge at 8-position. The developed QSAR models were applicable to estimate genotoxicity of quinolones antibiotics and their transformation products. It is noted that some of the transformation products exhibited higher genotoxicity comparing to their precursor (e.g., ciprofloxacin). This study provided an alternative way to understand the molecule genotoxicity of quinolones derivatives, as well as to evaluate their potential environmental risks.

  6. An artemisinin-derived dimer has highly potent anti-cytomegalovirus (CMV and anti-cancer activities.

    Directory of Open Access Journals (Sweden)

    Ran He

    Full Text Available We recently reported that two artemisinin-derived dimers (dimer primary alcohol 606 and dimer sulfone 4-carbamate 832-4 are significantly more potent in inhibiting human cytomegalovirus (CMV replication than artemisinin-derived monomers. In our continued evaluation of the activities of artemisinins in CMV inhibition, twelve artemisinin-derived dimers and five artemisinin-derived monomers were used. Dimers as a group were found to be potent inhibitors of CMV replication. Comparison of CMV inhibition and the slope parameter of dimers and monomers suggest that dimers are distinct in their anti-CMV activities. A deoxy dimer (574, lacking the endoperoxide bridge, did not have any effect on CMV replication, suggesting a role for the endoperoxide bridge in CMV inhibition. Differences in anti-CMV activity were observed among three structural analogs of dimer sulfone 4-carbamate 832-4 indicating that the exact placement and oxidation state of the sulfur atom may contribute to its anti-CMV activity. Of all tested dimers, artemisinin-derived diphenyl phosphate dimer 838 proved to be the most potent inhibitor of CMV replication, with a selectivity index of approximately 1500, compared to our previously reported dimer sulfone 4-carbamate 832-4 with a selectivity index of about 900. Diphenyl phosphate dimer 838 was highly active against a Ganciclovir-resistant CMV strain and was also the most active dimer in inhibition of cancer cell growth. Thus, diphenyl phosphate dimer 838 may represent a lead for development of a highly potent and safe anti-CMV compound.

  7. The safety of quinolones in pregnancy.

    Science.gov (United States)

    Yefet, Enav; Salim, Raed; Chazan, Bibiana; Akel, Hiba; Romano, Shabtai; Nachum, Zohar

    2014-11-01

    Quinolones and fluoroquinolones are highly efficient antibiotics. However, concerns regarding possible harmful effects have limited their use during pregnancy. Nevertheless, accumulating clinical data suggest that they may be safe during pregnancy. This review aimed to explore the mechanisms of action of the quinolones and fluoroquinolones, which set the stage for concerns regarding possible teratogenic and mutagenic effects; to clarify the clinical dilemmas that brought forth the necessity in reevaluating the use of those medications during pregnancy; and to review the accumulated data regarding their safety during pregnancy in animal models and humans.

  8. Copper-obatoclax derivative complexes mediate DNA cleavage and exhibit anti-cancer effects in hepatocellular carcinoma.

    Science.gov (United States)

    Su, Jung-Chen; Chang, Jung-Hua; Huang, Jui-Wen; Chen, Peter P-Y; Chen, Kuen-Feng; Tseng, Ping-Hui; Shiau, Chung-Wai

    2015-02-25

    Obatoclax is an indole-pyrrole compound that induces cancer cell apoptosis through targeting the anti-apoptotic Bcl-2 protein family. Previously, we developed a series of obatoclax derivatives and studied their STAT3 inhibition-dependent activity against cancer cell lines. The obatoclax analog, prodigiosin, has been reported to mediate DNA cleavage in cancer cells by coordinating with copper complexes. To gain an understanding of copper-obatoclax complex activity, we applied obatoclax derivatives to examine their copper-mediated nuclease activity as a means to establish a basis for structure activity relationship. Replacement of the indole ring of obatoclax with furanyl, thiophenyl or Boc-indolyl rings reduced the DNA cleavage ability. The same effect was achieved through the replacement of the obatoclax pyrrolyl ring with thiazolidinedione and thioacetal. Among the compounds tested, we demonstrated that the complex of obatoclax or compound 7 with copper exhibited potent DNA strand scission which correlated with HCC cell growth inhibition.

  9. Synthesis and QSAR Study of Novel 6-Chloro-3-(2-Arylmethylene-1-methylhydrazino-1,4,2-benzodithiazine 1,1-Dioxide Derivatives with Anticancer Activity

    Directory of Open Access Journals (Sweden)

    Jarosław Sławiński

    2015-04-01

    Full Text Available A series of new 6-chloro-3-(2-arylmethylene-1-methylhydrazino-1,4,2-benzodithiazine 1,1-dioxide derivatives were effectively synthesized from N-methyl-N-(6-chloro-1,1-dioxo-1,4,2-benzodithiazin-3-ylhydrazines. The intermediate compounds as well as the products, were evaluated for their cytotoxic effects toward three human cancer cell lines. All compounds shown moderate or weak cytotoxic effects against the tested cancer cell lines, but selective cytotoxic effects were observed. Compound 16 exhibited the most potent cytotoxic activity against the HeLa cell line, with an IC50 value of 10 µM, while 14 was the most active against the MCF-7 and HCT-116 cell lines, affording IC50 values of 15 µM and 16 µM, respectively. The structure-activity relationship was evaluated based on QSAR methodology. The QSAR MCF-7 model indicated that natural charge on carbon atom C13 and energy of highest occupied molecular orbital (HOMO are highly involved in cytotoxic activity against MCF-7 cell line. The cytotoxic activity of compounds against HCT-116 cell line is dependent on natural charge on carbon atom C13 and electrostatic charge on nitrogen atom N10. The obtained QSAR models could provide guidelines for further development of novel anticancer agents.

  10. 2,4-dihydroxy benzaldehyde derived Schiff bases as small molecule Hsp90 inhibitors: rational identification of a new anticancer lead.

    Science.gov (United States)

    Dutta Gupta, Sayan; Revathi, B; Mazaira, Gisela I; Galigniana, Mario D; Subrahmanyam, C V S; Gowrishankar, N L; Raghavendra, N M

    2015-04-01

    Hsp90 is a molecular chaperone that heals diverse array of biomolecules ranging from multiple oncogenic proteins to the ones responsible for development of resistance to chemotherapeutic agents. Moreover they are over-expressed in cancer cells as a complex with co-chaperones and under-expressed in normal cells as a single free entity. Hence inhibitors of Hsp90 will be more effective and selective in destroying cancer cells with minimum chances of acquiring resistance to them. In continuation of our goal to rationally develop effective small molecule azomethines against Hsp90, we designed few more compounds belonging to the class of 2,4-dihydroxy benzaldehyde derived imines (1-13) with our validated docking protocol. The molecules exhibiting good docking score were synthesized and their structures were confirmed by IR, (1)H NMR and mass spectral analysis. Subsequently, they were evaluated for their potential to suppress Hsp90 ATPase activity by Malachite green assay. The antiproliferative effect of the molecules were examined on PC3 prostate cancer cell lines by adopting 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay methodology. Finally, schiff base 13 emerged as the lead molecule for future design and development of Hsp90 inhibitors as anticancer agents.

  11. Synthesis and Anticancer Activity of Some Novel Tetralin-6-yl-pyrazoline, 2-Thioxopyrimidine, 2-Oxopyridine, 2-Thioxo-pyridine and 2-Iminopyridine Derivatives

    Directory of Open Access Journals (Sweden)

    Ebtehal S. Al-Abdullah

    2011-04-01

    Full Text Available The title compounds were prepared by reaction of 6-acetyltetralin (1 with different aromatic aldehydes 2a-c, namely 2,6-dichlorobenzaldehyde, 2,6-diflouro-benzaldehyde, and 3-ethoxy-4-hydroxybenzaldehyde, to yield the corresponding a,b-unsaturated ketones 3a-c. Compound 3b was reacted with hydrazine hydrate to yield the corresponding 2-pyrazoline 4, while compounds 3a,b reacted with thiourea to afford the 2-thioxopyrimidine derivatives 5a,b, respectively. The reaction of 1, and the aromatic aldehydes 2a-c with ethyl cyanoacetate, 2-cyano-thioacetamide or malononitrile in the presence of ammonium acetate yielded the corresponding 2-oxopyridines 6a,b, 2-thioxopyridines 7a-c or 2-iminopyridines 8a,b, respectively. The newly prepared compounds were evaluated for anticancer activity against two human tumor cell lines. Compound 3a showed the highest potency with IC50 = 3.5 and 4.5 μg/mL against a cervix carcinoma cell line (Hela and breast carcinoma cell line (MCF7, respectively.

  12. Quinolone-resistance in Salmonella is associated with decreased mRNA expression of virulence genes invA and avrA, growth and intracellular invasion and survival.

    Science.gov (United States)

    Wang, Yu-Ping; Li, Lin; Shen, Jian-Zhong; Yang, Fu-Jiang; Wu, Yong-Ning

    2009-02-01

    A variety of environmental factors, such as oxygen, pH, osmolarity and antimicrobial agents, modulate the expression of Salmonella pathogenicity islands (SPI) genes. This study investigated SPI-1 gene expression and the pathogenicity of quinolone-resistant Salmonella. mRNA expression levels of the invA and avrA genes, located in SPI-1, in quinolone-susceptible and quinolone-resistant Salmonella strains were determined using real-time fluorescent quantitative reverse transcription-polymerase chain reaction (RT-PCR). Twenty-five quinolone-resistant Salmonella mutants were derived from quinolone-susceptible strains by multiple-passage selection through increasing concentrations of ciprofloxacin in vitro, while an additional 15 strains were quinolone-resistant Salmonella clinical isolates. Sequence analysis showed no gene deletion or point mutations of nine SPI-1 genes (including invA and avrA) occurred in either the selected or clinical quinolone-resistant strains, while a single gyrA point mutation (S83F) was observed in all 40 quinolone-resistant strains. The mRNA expression levels of invA and avrA were significantly decreased (P<0.005) in quinolone-resistant strains (clinically acquired or experimentally selected in vitro), compared to the quinolone-susceptible strains. The resistant strains also had a slower growth rate combined with decreased epithelial cell invasion and intracellular replication in epithelial cells and macrophages. The results suggest that quinolone-resistance may be associated with lower virulence and pathogenicity than in quinolone-susceptible strains.

  13. The Current Case of Quinolones: Synthetic Approaches and Antibacterial Activity.

    Science.gov (United States)

    Naeem, Abdul; Badshah, Syed Lal; Muska, Mairman; Ahmad, Nasir; Khan, Khalid

    2016-03-28

    Quinolones are broad-spectrum synthetic antibacterial drugs first obtained during the synthesis of chloroquine. Nalidixic acid, the prototype of quinolones, first became available for clinical consumption in 1962 and was used mainly for urinary tract infections caused by Escherichia coli and other pathogenic Gram-negative bacteria. Recently, significant work has been carried out to synthesize novel quinolone analogues with enhanced activity and potential usage for the treatment of different bacterial diseases. These novel analogues are made by substitution at different sites--the variation at the C-6 and C-8 positions gives more effective drugs. Substitution of a fluorine atom at the C-6 position produces fluroquinolones, which account for a large proportion of the quinolones in clinical use. Among others, substitution of piperazine or methylpiperazine, pyrrolidinyl and piperidinyl rings also yields effective analogues. A total of twenty six analogues are reported in this review. The targets of quinolones are two bacterial enzymes of the class II topoisomerase family, namely gyrase and topoisomerase IV. Quinolones increase the concentration of drug-enzyme-DNA cleavage complexes and convert them into cellular toxins; as a result they are bactericidal. High bioavailability, relative low toxicity and favorable pharmacokinetics have resulted in the clinical success of fluoroquinolones and quinolones. Due to these superior properties, quinolones have been extensively utilized and this increased usage has resulted in some quinolone-resistant bacterial strains. Bacteria become resistant to quinolones by three mechanisms: (1) mutation in the target site (gyrase and/or topoisomerase IV) of quinolones; (2) plasmid-mediated resistance; and (3) chromosome-mediated quinolone resistance. In plasmid-mediated resistance, the efflux of quinolones is increased along with a decrease in the interaction of the drug with gyrase (topoisomerase IV). In the case of chromosome

  14. The Current Case of Quinolones: Synthetic Approaches and Antibacterial Activity

    Directory of Open Access Journals (Sweden)

    Abdul Naeem

    2016-03-01

    Full Text Available Quinolones are broad-spectrum synthetic antibacterial drugs first obtained during the synthesis of chloroquine. Nalidixic acid, the prototype of quinolones, first became available for clinical consumption in 1962 and was used mainly for urinary tract infections caused by Escherichia coli and other pathogenic Gram-negative bacteria. Recently, significant work has been carried out to synthesize novel quinolone analogues with enhanced activity and potential usage for the treatment of different bacterial diseases. These novel analogues are made by substitution at different sites—the variation at the C-6 and C-8 positions gives more effective drugs. Substitution of a fluorine atom at the C-6 position produces fluroquinolones, which account for a large proportion of the quinolones in clinical use. Among others, substitution of piperazine or methylpiperazine, pyrrolidinyl and piperidinyl rings also yields effective analogues. A total of twenty six analogues are reported in this review. The targets of quinolones are two bacterial enzymes of the class II topoisomerase family, namely gyrase and topoisomerase IV. Quinolones increase the concentration of drug-enzyme-DNA cleavage complexes and convert them into cellular toxins; as a result they are bactericidal. High bioavailability, relative low toxicity and favorable pharmacokinetics have resulted in the clinical success of fluoroquinolones and quinolones. Due to these superior properties, quinolones have been extensively utilized and this increased usage has resulted in some quinolone-resistant bacterial strains. Bacteria become resistant to quinolones by three mechanisms: (1 mutation in the target site (gyrase and/or topoisomerase IV of quinolones; (2 plasmid-mediated resistance; and (3 chromosome-mediated quinolone resistance. In plasmid-mediated resistance, the efflux of quinolones is increased along with a decrease in the interaction of the drug with gyrase (topoisomerase IV. In the case of

  15. Cyclopentadienyl-ruthenium(II) and iron(II) organometallic compounds with carbohydrate derivative ligands as good colorectal anticancer agents.

    Science.gov (United States)

    Florindo, Pedro R; Pereira, Diane M; Borralho, Pedro M; Rodrigues, Cecília M P; Piedade, M F M; Fernandes, Ana C

    2015-05-28

    New ruthenium(II) and iron(II) organometallic compounds of general formula [(η(5)-C5H5)M(PP)Lc][PF6], bearing carbohydrate derivative ligands (Lc), were prepared and fully characterized and the crystal structures of five of those compounds were determined by X-ray diffraction studies. Cell viability of colon cancer HCT116 cell line was determined for a total of 23 organometallic compounds and SAR's data analysis within this library showed an interesting dependency of the cytotoxic activity on the carbohydrate moiety, linker, phosphane coligands, and metal center. More importantly, two compounds, 14Ru and 18Ru, matched oxaliplatin IC50 (0.45 μM), the standard metallodrug used in CC chemotherapeutics, and our leading compound 14Ru was shown to be significantly more cytotoxic than oxaliplatin to HCT116 cells, triggering higher levels of caspase-3 and -7 activity and apoptosis in a dose-dependent manner.

  16. Plasmid mediated quinolone resistance in Enterobacteriaceae

    NARCIS (Netherlands)

    Veldman, K.T.; LS Klinisch Onderzoek Wagenaar

    2014-01-01

    This thesis describes the occurrence of Plasmid Mediated Quinolone Resistance (PMQR) in Salmonella and E. coli from The Netherlands and other European countries. Furthermore, the genetic background of these genes was characterized. Fluoroquinolones are widely used antibiotics in both human and veter

  17. Proficiency study for quinolones in egg

    NARCIS (Netherlands)

    Berendsen, B.J.A.; Stolker, A.A.M.

    2008-01-01

    Studie naar het voorkomen van quinolonen in eieren, beschrijving van de testmaterialen, evaluatie van de toegepaste methoden, resultaten en discussieThe aim of this proficiency study was to give laboratories the possibility to evaluate or demonstrate their competence for the analysis of quinolones i

  18. In vivo detection of human TRPV6-rich tumors with anti-cancer peptides derived from soricidin.

    Directory of Open Access Journals (Sweden)

    Chris V Bowen

    Full Text Available Soricidin is a 54-amino acid peptide found in the paralytic venom of the northern short-tailed shrew (Blarina brevicauda and has been found to inhibit the transient receptor potential of vallinoid type 6 (TRPV6 calcium channels. We report that two shorter peptides, SOR-C13 and SOR-C27, derived from the C-terminus of soricidin, are high-affinity antagonists of human TRPV6 channels that are up-regulated in a number of cancers. Herein, we report molecular imaging methods that demonstrate the in vivo diagnostic potential of SOR-C13 and SOR-C27 to target tumor sites in mice bearing ovarian or prostate tumors. Our results suggest that these novel peptides may provide an avenue to deliver diagnostic and therapeutic reagents directly to TRPV6-rich tumors and, as such, have potential applications for a range of carcinomas including ovarian, breast, thyroid, prostate and colon, as well as certain leukemia's and lymphomas.

  19. Anti-Cancer Activity of Resveratrol and Derivatives Produced by Grapevine Cell Suspensions in a 14 L Stirred Bioreactor

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    Laetitia Nivelle

    2017-03-01

    Full Text Available In the present study, resveratrol and various oligomeric derivatives were obtained from a 14 L bioreactor culture of elicited grapevine cell suspensions (Vitis labrusca L.. The crude ethyl acetate stilbene extract obtained from the culture medium was fractionated by centrifugal partition chromatography (CPC using a gradient elution method and the major stilbenes contained in the fractions were subsequently identified by using a 13C-NMR-based dereplication procedure and further 2D NMR analyses including HSQC, HMBC, and COSY. Beside δ-viniferin (2, leachianol F (4 and G (4′, four stilbenes (resveratrol (1, ε-viniferin (5, pallidol (3 and a newly characterized dimer (6 were recovered as pure compounds in sufficient amounts to allow assessment of their biological activity on the cell growth of three different cell lines, including two human skin malignant melanoma cancer cell lines (HT-144 and SKMEL-28 and a healthy human dermal fibroblast HDF line. Among the dimers obtained in this study, the newly characterized resveratrol dimer (6 has never been described in nature and its biological potential was evaluated here for the first time. ε-viniferin as well as dimer (6 showed IC50 values on the three tested cell lines lower than the ones exerted by resveratrol and pallidol. However, activities of the first two compounds were significantly decreased in the presence of fetal bovine serum although that of resveratrol and pallidol was not. The differential tumor activity exerted by resveratrol on healthy and cancer lines was also discussed.

  20. New Marine Derived Anticancer Therapeutics ─ A Journey from the Sea to Clinical Trials

    Directory of Open Access Journals (Sweden)

    J. Jimeno

    2004-02-01

    Full Text Available Abstract: Nature has been instrumental as a source for therapeutics. Despite the fact that we live in an oceanic planet, a number of technical factors have historically hampered the evolution of a marine-based chamanic medicine. With the implementation of scuba diving tools and the development of sophisticated instruments for the isolation and elucidation of structures of natural products from marine organisms, major advances have been made in the discovery of marine derived therapeutics. The availability of ARA-C, a nucleoside analog that is a basic component in the treatment of acute myeloid leukemia, and its fluorinated analog Gemcitabine, an important therapeutic tool in the treatment of pancreatic cancer and in non small cell lung cancer, is a solid proof and validation of the potential of this approach. As a result of our discovery and developmental program, three innovative compounds with novel mechanisms of action: ET-743, AplidinR and Kahalalide F, have been shown to display a positive therapeutic index and activity in resistant solid tumors that supports the ongoing clinical phase III/II trials. ET-743 represents the first active agent against sarcomas developed in the past 25 years and has demonstrated a therapeutic potential in pretreated ovarian cancer. Several chemical entities are under advanced preclinical testing and additional candidates for clinical development are emerging, including compounds hitting a specific target. Moreover, the development of a given marine candidate implies the collaboration of an interdisciplinary team special focused on supply, formulation, pharmacogenetics and preclinical toxicology.

  1. Sesterterpenoids with Anticancer Activity.

    Science.gov (United States)

    Evidente, Antonio; Kornienko, Alexander; Lefranc, Florence; Cimmino, Alessio; Dasari, Ramesh; Evidente, Marco; Mathieu, Véronique; Kiss, Robert

    2015-01-01

    Terpenes have received a great deal of attention in the scientific literature due to complex, synthetically challenging structures and diverse biological activities associated with this class of natural products. Based on the number of C5 isoprene units they are generated from, terpenes are classified as hemi- (C5), mono- (C10), sesqui- (C15), di- (C20), sester- (C25), tri (C30), and tetraterpenes (C40). Among these, sesterterpenes and their derivatives known as sesterterpenoids, are ubiquitous secondary metabolites in fungi, marine organisms, and plants. Their structural diversity encompasses carbotricyclic ophiobolanes, polycyclic anthracenones, polycyclic furan-2-ones, polycyclic hydroquinones, among many other carbon skeletons. Furthermore, many of them possess promising biological activities including cytotoxicity and the associated potential as anticancer agents. This review discusses the natural sources that produce sesterterpenoids, provides sesterterpenoid names and their chemical structures, biological properties with the focus on anticancer activities and literature references associated with these metabolites. A critical summary of the potential of various sesterterpenoids as anticancer agents concludes the review.

  2. Saponins from Chinese Medicines as Anticancer Agents

    Directory of Open Access Journals (Sweden)

    Xiao-Huang Xu

    2016-10-01

    Full Text Available Saponins are glycosides with triterpenoid or spirostane aglycones that demonstrate various pharmacological effects against mammalian diseases. To promote the research and development of anticancer agents from saponins, this review focuses on the anticancer properties of several typical naturally derived triterpenoid saponins (ginsenosides and saikosaponins and steroid saponins (dioscin, polyphyllin, and timosaponin isolated from Chinese medicines. These saponins exhibit in vitro and in vivo anticancer effects, such as anti-proliferation, anti-metastasis, anti-angiogenesis, anti-multidrug resistance, and autophagy regulation actions. In addition, related signaling pathways and target proteins involved in the anticancer effects of saponins are also summarized in this work.

  3. Synthesis, spectroscopic characterization and in vitro antimicrobial, anticancer and antileishmanial activities as well interaction with Salmon sperm DNA of newly synthesized carboxylic acid derivative, 4-(4-methoxy-2-nitrophenylamino)-4-oxobutanoic acid.

    Science.gov (United States)

    Sirajuddin, Muhammad; Ali, Saqib; McKee, Vickie; Ullah, Hameed

    2015-03-05

    This paper stresses on the synthesis, characterization of novel carboxylic acid derivative and its application in pharmaceutics. Carboxylic acid derivatives have a growing importance in medicine, particularly in oncology. A novel carboxylic acid, 4-(4-methoxy-2-nitrophenylamino)-4-oxobutanoic acid, was synthesized and characterized by elemental analysis, FT-IR, NMR ((1)H, and (13)C), mass spectrometry and single crystal X-ray structural analysis. The structure of the title compound, C11H12N2O6, shows the molecules dimerised by short intramolecular OH⋯O hydrogen bonds. The compound was screened for in vitro antimicrobial, anticancer, and antileishmanial activities as well as interaction with SS-DNA. The compound was also checked for in vitro anticancer activity against BHK-21, H-157 and HCEC cell lines, and showed significant anticancer activity. The compound was almost non-toxic towards human corneal epithelial cells (HCEC) and did not show more than 7.4% antiproliferative activity when used at the 2.0μg/mL end concentration. It was also tested for antileishmanial activity against the promastigote form of leishmania major and obtained attractive result. DNA interaction study exposes that the binding mode of the compound with SS-DNA is an intercalative as it results in hypochromism along with minor red shift. A new and efficient strategy to identify pharmacophores sites in carboxylic acid derivative for antibacterial/antifungal activity using Petra, Osiris and Molinspiration (POM) analyses was also carried out.

  4. Heterocyclic chalcone analogues as potential anticancer agents.

    Science.gov (United States)

    Sharma, Vikas; Kumar, Vipin; Kumar, Pradeep

    2013-03-01

    Chalcones, aromatic ketones and enones acting as the precursor for flavonoids such as Quercetin, are known for their anticancer effects. Although, parent chalcones consist of two aromatic rings joined by a three-carbon α,β-unsaturated carbonyl system, various synthetic compounds possessing heterocyclic rings like pyrazole, indole etc. are well known and proved to be effective anticancer agents. In addition to their use as anticancer agents in cancer cell lines, heterocyclic analogues are reported to be effective even against resistant cell lines. In this connection, we hereby highlight the potential of various heterocyclic chalcone analogues as anticancer agents with a brief summary about therapeutic potential of chalcones, mechanism of anticancer action of various chalcone analogues, and current and future prospects related to the chalcones-derived anticancer research. Furthermore, some key points regarding chalcone analogues have been reviewed by analyzing their medicinal properties.

  5. Using SAR and QSAR analysis to model the activity and structure of the quinolone-DNA complex.

    Science.gov (United States)

    Llorente, B; Leclerc, F; Cedergren, R

    1996-01-01

    A set of 78 quinolone derivatives were used in a structure-activity study to identify structural features correlating with antibacterial activity. Distinct combinations of functional properties were identified for Gram-negative and Gram-positive bacteria. 3-D Quantitative structure-activity relationship (QSAR) studies identified specific hydrophobic, topologic and electronic properties of the molecules for both in vitro and in vivo activities. From these results, a three-dimensional model of a DNA-quinolone complex was built using molecular modeling techniques. It was based on the intercalation of quinolone into the double helix of DNA. We conclude that the intercalation model is consistent with most available data on the structure of the quinolone complex. This predicted structure is stabilized by the binding of magnesium ion with the sp2 oxygens present in quinolone, a phosphate and a purine base of the DNA. Substituents R1 and R7 are predicted to make hydrophobic interactions in the major and minor groove of DNA, respectively. R7 could also form hydrogen bonds with amino groups of guanines and the aspartic acid residue at position 87 in DNA gyrase subunit A.

  6. Topoisomerase IV-quinolone interactions are mediated through a water-metal ion bridge: mechanistic basis of quinolone resistance.

    Science.gov (United States)

    Aldred, Katie J; McPherson, Sylvia A; Turnbough, Charles L; Kerns, Robert J; Osheroff, Neil

    2013-04-01

    Although quinolones are the most commonly prescribed antibacterials, their use is threatened by an increasing prevalence of resistance. The most common causes of quinolone resistance are mutations of a specific serine or acidic residue in the A subunit of gyrase or topoisomerase IV. These amino acids are proposed to serve as a critical enzyme-quinolone interaction site by anchoring a water-metal ion bridge that coordinates drug binding. To probe the role of the proposed water-metal ion bridge, we characterized wild-type, GrlA(E85K), GrlA(S81F/E85K), GrlA(E85A), GrlA(S81F/E85A) and GrlA(S81F) Bacillus anthracis topoisomerase IV, their sensitivity to quinolones and related drugs and their use of metal ions. Mutations increased the Mg(2+) concentration required to produce maximal quinolone-induced DNA cleavage and restricted the divalent metal ions that could support quinolone activity. Individual mutation of Ser81 or Glu85 partially disrupted bridge function, whereas simultaneous mutation of both residues abrogated protein-quinolone interactions. Results provide functional evidence for the existence of the water-metal ion bridge, confirm that the serine and glutamic acid residues anchor the bridge, demonstrate that the bridge is the primary conduit for interactions between clinically relevant quinolones and topoisomerase IV and provide a likely mechanism for the most common causes of quinolone resistance.

  7. Novel ferrocenyl derivatives exert anti-cancer effect in human lung cancer cells in vitro via inducing G1-phase arrest and senescence

    Institute of Scientific and Technical Information of China (English)

    Ying LI; Han-lin MA; Lei HAN; Wei-yong LIU; Bao-xiang ZHAO; Shang-li ZHANG; Jun-ying MIAO

    2013-01-01

    Aim:To investigate the effects of 7 novel 1-ferrocenyl-2-(5-phenyl-1H-1,2,4-triazol-3-ylthio) ethanone derivatives on human lung cancer cells in vitro and to determine the mechanisms of action.Methods:A549 human lung cancer cells were examined.Cell viability was analyzed with MTT assay.Cell apoptosis and senescence were examined using Hoechst 33258 and senescence-associated-β-galactosidase (SA-β-gal) staining,respectively.LDH release was measured using a detection kit.Cell cycle was analyzed using a flow cytometer.Intracellular ROS level was measured with the 2',7'-dichlorodihydrofluorescein probe.Phosphorylation of p38 was determined using Western blot.Results:Compounds 5b,5d,and 5e (40 and 80 μmol/L) caused significant decrease of A549 cell viability,while other 4 compounds had no effect on the cells.Compounds 5b,5d,and 5e (80 μmol/L) induced G1-phase arrest (increased the G1 population by 22.6%,24.23%,and 26.53%,respectively),and markedly increased SA-β-gal-positive cells.However,the compounds did not cause nuclear DNA fragmentation and chromatin condensation in A549 cells.Nor did they affect the release of LDH from the cells.The compounds significantly elevated the intracellular ROS level,decreased the mitochondrial membrane potential,and increased p38 phosphorylation in the cells.In the presence of the antioxidant and free radical scavenger N-acetyl-L-cysteine (10 mmol/L),above effects of compounds 5b,5d,and 5e were abolished.Conclusion:The compounds 5b,5d,and 5e cause neither apoptosis nor necrosis of A549 cells,but exert anti-cancer effect via inducing G1-phase arrest and senescence through ROS/p38 MAP-kinase pathway.

  8. Stereoselective Synthesis and Anticancer Activities of New Podophyllotoxin Derivatives: 4-β -Cyano-4-Deoxy-4'-Demethylepipodophyllotoxin and 4-β -Carboxyl-4-Deoxy-4'-Demethylepipodophyllotoxin

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    4-β -Cyano-4-deoxy-4'-demethylepipodophyllotoxin 4 was synthesized from 4'-de -methylepipodophyllotoxin and Me3SiCN in the presence of BF3·Et2O. 4-β -Carboxyl-4-deoxy-4'-demethylepipodophyllotoxin 5 was obtained by hydrolyzing 4 in HOAc. Both of them show very high anticancer activities against L1210 and KB cell lines in vitro.

  9. Regional variations in quinolone use in France and associated factors.

    Science.gov (United States)

    Gallini, A; Taboulet, F; Bourrel, R

    2012-11-01

    The purpose of this study was to investigate geographic variations in the use of quinolones in France and their associated factors. All reimbursement claims of antimicrobials were collected for 90 % of the French population for the year 2007. Dispensed quantities were then converted into defined daily doses (DDD) and adjusted for the age structure of the national population. Correlations between quinolone use and total antimicrobial use and some morbidity and socio-economic factors were studied using Spearman's rank correlation coefficients. On average, 2.05 DDD of quinolones per 1,000 inhabitants per day (DID) were dispensed in 2007 in France, accounting for 10.2 % of the total antimicrobial consumption in adults. A 40 % variation was observed between the regions with the lowest (1.73 DID) and the highest use (2.44 DID). This variation was more important for anti-pneumococcal quinolones than for quinolones directed against urinary tract infections (coefficients of variation: 26 vs. 6 %). Quinolone use was correlated with some regional socio-economic factors (unemployment, growth domestic product, health expenditures) and physician density, but was independent of the total antimicrobial use. After adjustment for age, large variations in quantitative and qualitative quinolone use were observed across French regions, especially for anti-pneumococcal fluoroquinolones. These results, though not controlled for potential epidemics variations, argue in favour of a possible improvement in quinolone prescribing to be achieved in some regions.

  10. New Role of Quinolones in Respiratory Tract Infections

    Directory of Open Access Journals (Sweden)

    Ronald F Grossman

    1998-01-01

    Full Text Available Because of limited activity of the standard quinolones such as ciprofloxacin and ofloxacin against some clinically important organisms including Streptococcus pneumoniae and methicillin-resistant Staphylococcus aureus, new quinolones have been developed. In addition to their improved activity against S pneumoniae, some also demonstrate excellent anaerobic activity. None of the quinolones have a role to play in the treatment of paediatric infections. Quinolones (both older and newer agents have demonstrated equivalent efficacy to standard antimicrobials in the treatment of acute sinusitis. Several groups have suggested that quinolones are excellent agents in the treatment of high risk patients with acute exacerbations of chronic bronchitis. These patients include the elderly, and those with frequent exacerbations, significant comorbid conditions. long duration of chronic bronchitis and major impairment of lung function. There is no evidence to suggest that the newer quinolones will differ from the currently available agents for th is disease. The major advantage of the newer quinolones appears to be in the treatment of patients with community-acquired pneumonia where pneumococcal infection is a real concern. A new parenteral quinolone with pneumococcal activity may replace the standard macrolide/cephalosporin combination that is commonly prescribed. For patients with nosocomial pneumonia, the newer agents are alternative choices, especially among patients with early onset pneumonia (less than five days of hospitalization, but are unlikely to replace ciprofloxacin in the intensive care unit setting because of poor Pseudomonas aeruginosa coverage.

  11. 1,10-菲咯啉及其衍生物铜配合物的抗癌活性研究进展%Progress of Anticancer Activities of Copper Complexes with1,10-Phenanthroline and its Derivatives

    Institute of Scientific and Technical Information of China (English)

    夏寺丰; 鲁晓明

    2011-01-01

    As bio-essential trace element,copper plays an important role in biological processes,and many copper complexes have the activity of anti-proliferation of cancer cells.The progress in anti-cancer activity of copper complexes with 1,10-phenanthroline and its derivatives was reviewed,and the proposal mechanism of oxidative cleavage of DNA by different sorts of copper complexes was discussed.In addition,the prospects of copper complexes as anti-cancer drugs were presented by comparison with cisplatin anti-cancer drugs.%作为一种微量生命元素,铜在生物进程中扮演着重要角色,很多铜配合物呈现抑制癌细胞增殖的活性。本文论述了以1,10-菲咯啉及其衍生物为配体的铜配合物的抗癌活性研究进展,分析了其对DNA裂解的可能机理。对比顺铂类抗癌药物,展望了铜配合物作为抗癌药物的应用前景。

  12. Novel anticancer agents from plant sources

    Institute of Scientific and Technical Information of China (English)

    Shah Unnati; Shah Ripal; Acharya Sanjeev; Acharya Niyati

    2013-01-01

    Plants remain an important source of new drugs,new drug leads and new chemical entities.Plant based drug discovery resulted mainly in the development of anticancer and anti-infectious agents,and continues to contribute to the new leads in clinical trials.Natural product drugs play a dominant role in pharmaceutical care.Several plant-derived compounds are currently successfully employed in cancer treatment.There are many classes of plant-derived cytotoxic natural products studied for further improvement and development of drugs.New anticancer drugs derived from research on plant antitumor agents will be continuously discovered.The basic aim of this review is to explore the potential of newly discovered anticancer compounds from medicinal plants,as a lead for anticancer drug development.It will be helpful to explore the medicinal value of plants and for new drug discovery from them for the researchers and scientists around the globe.

  13. Glutamic acid as anticancer agent: An overview.

    Science.gov (United States)

    Dutta, Satyajit; Ray, Supratim; Nagarajan, K

    2013-10-01

    The objective of the article is to highlight various roles of glutamic acid like endogenic anticancer agent, conjugates to anticancer agents, and derivatives of glutamic acid as possible anticancer agents. Besides these emphases are given especially for two endogenous derivatives of glutamic acid such as glutamine and glutamate. Glutamine is a derivative of glutamic acid and is formed in the body from glutamic acid and ammonia in an energy requiring reaction catalyzed by glutamine synthase. It also possesses anticancer activity. So the transportation and metabolism of glutamine are also discussed for better understanding the role of glutamic acid. Glutamates are the carboxylate anions and salts of glutamic acid. Here the roles of various enzymes required for the metabolism of glutamates are also discussed.

  14. Antibacterial action of quinolones: from target to network.

    Science.gov (United States)

    Cheng, Guyue; Hao, Haihong; Dai, Menghong; Liu, Zhenli; Yuan, Zonghui

    2013-08-01

    Quinolones are widely used broad-spectrum antibacterials with incomplete elucidated mechanism of action. Here, molecular basis for the antibacterial action of quinolones, from target to network, is fully discussed and updated. Quinolones trap DNA gyrase or topoisomerase IV to form reversible drug-enzyme-DNA cleavage complexes, resulting in bacteriostasis. Cell death arises from chromosome fragmentation in protein synthesis-dependent or -independent pathways according to distinguished quinolone structures. In the former pathway, irreversible oxidative DNA damage caused by reactive oxygen species kills bacteria eventually. Toxin-antitoxin mazEF is triggered as an additional lethal action. Bacteria survive and develop resistance by SOS and other stress responses. Enlarged knowledges of quinolone actions and bacterial response will provide new targets for drug design and approaches to prevent bacterial resistance.

  15. Affinity of 3-acyl substituted 4-quinolones at the benzodiazepine site of GABAA receptors

    DEFF Research Database (Denmark)

    Lager, Erik; Nilsson, Jakob; Nielsen, Elsebet Østergaard

    2008-01-01

    The finding that alkyl 1,4-dihydro-4-oxoquinoline-3-carboxylate and N-alkyl-1,4-dihydro-4-oxoquinoline-3-carboxamide derivatives may be high-affinity ligands at the benzodiazepine binding site of the GABA(A) receptor, prompted a study of 3-acyl-1,4-dihydro-4-oxoquinoline (3-acyl-4-quinolones......). In general, the affinity of the 3-acyl derivatives was found to be comparable with the 3-carboxylate and the 3-carboxamide derivatives, and certain substituents (e.g., benzyl) in position 6 were again shown to be important. As it is believed that the benzodiazepine binding site is situated between an alpha...

  16. Vibrational spectra study on quinolones antibiotics

    Science.gov (United States)

    Wang, Yu; Yu, Ke; Wang, Sihuan

    2006-09-01

    In order to be able to fully understand and easily identify the quilonoles, we collected IR and Raman spectra of six quinolones, and attempted to assign the attribution of the observed frequencies and their association with specific modes of vibration. According to the structure, the compounds were divided into the groups, and the similarities and differences were further studied by comparing. The result of the study shows that the frequency and intensity are comparable to the corresponding structure. The spectra not only have the commonness but also the individualities.

  17. Crude Extracts of Marine-derived and Soil Fungi of the Genus Neosartorya Exhibit Selective Anticancer Activity by Inducing Cell Death in Colon, Breast and Skin Cancer Cell Lines

    OpenAIRE

    Alice Abreu Ramos; Bruno Castro-Carvalho; Maria Prata-Sena; Tida Dethoup; Suradet Buttachon; Anake Kijjoa; Eduardo Rocha

    2016-01-01

    Background: The crude ethyl acetate extracts of marine-derived fungi Neosartorya tsunodae KUFC 9213 (E1) and N. laciniosa KUFC 7896 (E2), and soil fungus N. fischeri KUFC 6344 (E3) were evaluated for their in vitro anticancer activities on a panel of seven human cancer cell lines. Materials and Methods: The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed, after 48 h treatments with different concentrations of extracts, to determine their concentration of the e...

  18. A molecular analysis of quinolone-resistant Haemophilus influenzae: validation of the mutations in Quinolone Resistance-Determining Regions.

    Science.gov (United States)

    Shoji, Hisashi; Shirakura, Tetsuro; Fukuchi, Kunihiko; Takuma, Takahiro; Hanaki, Hideaki; Tanaka, Kazuo; Niki, Yoshihito

    2014-04-01

    The mechanism of quinolone-resistance is considered to be amino acid mutations in the type II topoisomerase. We validated the genetic mechanisms of quinolone resistance in Haemophilus influenzae. We obtained 29 H. influenzae strains from a nationwide surveillance program in Japan (including 11 quinolone-resistant strains [moxifloxacin: MFLX or levofloxacin MIC ≥2 μg/ml]). We analyzed the sequences of the Quinolone Resistance-Determining Regions (QRDRs) in GyrA, GyrB, ParC and ParE. Furthermore, we induced resistance in susceptible strains by exposing them to quinolone, and investigated the relationship between mutations in the QRDRs and the MICs. Five amino acid substitutions in GyrA (at Ser84 and Asp88) and ParC (at Gly82, Ser84 and Glu88) were found to be closely related to the MICs. The strains with a MFLX MIC of 0.125-1 and 2-4 μg/ml had one and two mutations, respectively. The strains with a MFLX MIC of ≥8 μg/ml had three or more mutations. The strains with induced resistance with MFLX MICs of 0.5-1 and ≥2 μg/ml also had one and two mutations, respectively. We confirmed that these five mutations strongly contribute to quinolone resistance and found that the degree of resistance is related to the number of the mutations. In addition, the three strains of 18 susceptible strains (16.7%) also had a single mutation. These strains may therefore be in the initial stage of quinolone resistance. Currently, the frequency of quinolone-resistant H. influenzae is still low. However, as has occurred with β-lactams, an increase in quinolone use may lead to more quinolone-resistant strains.

  19. Fungal metabolites with anticancer activity.

    Science.gov (United States)

    Evidente, Antonio; Kornienko, Alexander; Cimmino, Alessio; Andolfi, Anna; Lefranc, Florence; Mathieu, Véronique; Kiss, Robert

    2014-05-01

    Covering: 1964 to 2013. Natural products from bacteria and plants have played a leading role in cancer drug discovery resulting in a large number of clinically useful agents. In contrast, the investigations of fungal metabolites and their derivatives have not led to a clinical cancer drug in spite of significant research efforts revealing a large number of fungi-derived natural products with promising anticancer activity. Many of these natural products have displayed notable in vitro growth-inhibitory properties in human cancer cell lines and select compounds have been demonstrated to provide therapeutic benefits in mouse models of human cancer. Many of these compounds are expected to enter human clinical trials in the near future. The present review discusses the reported sources, structures and biochemical studies aimed at the elucidation of the anticancer potential of these promising fungal metabolites.

  20. Quinolone-containing therapies in the eradication of Helicobacter pylori.

    Science.gov (United States)

    Chuah, Seng-Kee; Tai, Wei-Chen; Lee, Chen-Hsiang; Liang, Chih-Ming; Hu, Tsung-Hui

    2014-01-01

    Fluoroquinolones, especially levofloxacin, are used in the eradication of Helicobacter pylori worldwide. Many consensus guidelines recommend that the second-line rescue therapy for H. pylori eradication consists of a proton pump inhibitor, a quinolone, and amoxicillin as an option. Unfortunately, quinolone is well associated with a risk of developing bacterial resistance. In this paper, we review quinolone-containing H. pylori eradication regimens and the challenges that influence the efficacy of eradication. It is generally suggested that the use of levofloxacin should be confined to "rescue" therapy only, in order to avoid a further rapid increase in the resistance of H. pylori to quinolone. The impact of quinolone-containing H. pylori eradication regimens on public health issues such as tuberculosis treatment must always be taken into account. Exposure to quinolone is relevant to delays in diagnosing tuberculosis and the development of drug resistance. Extending the duration of treatment to 14 days improves eradication rates by >90%. Tailored therapy to detect fluoroquinolone-resistant strains can be done by culture-based and molecular methods to provide better eradication rates. Molecular methods are achieved by using a real-time polymerase chain reaction to detect the presence of a gyrA mutation, which is predictive of treatment failure with quinolones-containing triple therapy.

  1. Microbial transformations of antimicrobial quinolones and related drugs.

    Science.gov (United States)

    Parshikov, Igor A; Sutherland, John B

    2012-12-01

    The quinolones are an important group of synthetic antimicrobial drugs used for treating bacterial diseases of humans and animals. Microorganisms transform antimicrobial quinolones (including fluoroquinolones) and the pharmacologically related naphthyridones, pyranoacridones, and cinnolones to a variety of metabolites. The biotransformation processes involve hydroxylation of methyl groups; hydroxylation of aliphatic and aromatic rings; oxidation of alcohols and amines; reduction of carboxyl groups; removal of methyl, carboxyl, fluoro, and cyano groups; addition of formyl, acetyl, nitrosyl, and cyclopentenone groups; and cleavage of aliphatic and aromatic rings. Most of these reactions greatly reduce or eliminate the antimicrobial activity of the quinolones.

  2. New quinoxaline 1,4-di-N-oxides. Part 1: Hypoxia-selective cytotoxins and anticancer agents derived from quinoxaline 1,4-di-N-oxides.

    Science.gov (United States)

    Amin, Kamelia M; Ismail, Magda M F; Noaman, Eman; Soliman, Dalia H; Ammar, Yousry A

    2006-10-15

    Hypoxic cells which are common feature of solid tumors are resistant to both anticancer drugs and radiation therapy. Thus, the identification of drugs with the selective toxicity toward hypoxic cells is an important target in anticancer chemotherapy. Tirapazamine has been shown to be an efficient and selective cytotoxin after bioreductive activation in hypoxic cells which is thought to be due to the presence of the 1,4-di-N-oxide. A new series of quinoxaline 1,4-di-N-oxides and fused quinoxaline di-N-oxides were synthesized and evaluated for hypoxic-cytotoxic activity on EAC cell line. Compound 10a was the most potent cytotoxin IC(50) 0.9 microg/mL, potency 75 microg/mL, and was approximately 15 times more selective cytotoxin (HCR>111) than 3-aminoquinoxaline-2-carbonitrile which has been used as a standard (HCR>7.5). Compounds 4 and 3a,b were more selective than the standard. In addition, antitumor activity against Hepg2 (liver) and U251 (brain) human cell lines was evaluated, compounds 9c and 8a were the most active against Hepg2 with IC(50) values 1.9 and 2.9 microg/mL, respectively, however, all the tested compounds were nontoxic against U251 cell line.

  3. Crude extracts of marine-derived and soil fungi of the genus Neosartorya exhibit selective anticancer activity by inducing cell death in colon, breast and skin cancer cell lines

    Directory of Open Access Journals (Sweden)

    Alice Abreu Ramos

    2016-01-01

    Full Text Available Background: The crude ethyl acetate extracts of marine-derived fungi Neosartorya tsunodae KUFC 9213 (E1 and N. laciniosa KUFC 7896 (E2, and soil fungus N. fischeri KUFC 6344 (E3 were evaluated for their in vitro anticancer activities on a panel of seven human cancer cell lines. Materials and Methods: The 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide assay was performed, after 48 h treatments with different concentrations of extracts, to determine their concentration of the extract or Dox that inhibits cell viability by 50% for each cell line. The effects of the crude extracts on DNA damage, clonogenic potential and their ability to induce cell death were also assessed. Results: E1 was found to the void of anti-proliferative effects. E2 was shown to decrease the clonogenic potential in human colorectal carcinoma cell line (HCT116, human malignant melanoma cell line (A375, human breast adenocarcinoma cell line (MCF7, and human caucasian colon adenocarcinoma Grade II cell line (HT29 cells, whereas E3 showed such effect only in HCT116 and MCF7 cells. Both extracts were found to increase DNA damage in some cell lines. E2 was found to induce cell death in HT29, HCT116, MCF7, and A375 cells while extract E3 increased cell death in MCF7 and HCT116 cell lines. Conclusion: The results reveal that E2 and E3 possess anticancer activities in human colon carcinoma, breast adenocarcinoma, and melanoma cells, validating the interest for an identification of molecular targets involved in the anticancer activity.

  4. Anticancer peptides from bacteria

    Directory of Open Access Journals (Sweden)

    Tomasz M. Karpiński

    2013-08-01

    Full Text Available Cancer is a leading cause of death in the world. The rapid development of medicine and pharmacology allows to create new and effective anticancer drugs. Among modern anticancer drugs are bacterial proteins. Until now has been shown anticancer activity among others azurin and exotoxin A from Pseudomonas aeruginosa, Pep27anal2 from Streptococcus pneumoniae, diphtheria toxin from Corynebacterium diphtheriae, and recently discovered Entap from Enterococcus sp. The study presents the current data regarding the properties, action and anticancer activity of listed peptides.

  5. Increasing quinolone resistance in Salmonella enterica serotype enteritidis

    DEFF Research Database (Denmark)

    Mølbak, K.; Gerner-Smidt, P.; Wegener, Henrik Caspar

    2002-01-01

    Until recently, Salmonella enterica serotype Enteritidis has remained sensitive to most antibiotics. However, national surveillance data from Denmark show that quinolone resistance in S. Enteritidis has increased from 0.8% in 1995 to 8.5% in 2000. These data support concerns that the current use...... of quinolone in food animals leads to increasing resistance in S. Enteritidis and that action should be taken to limit such use....

  6. New cytotoxic quinolone alkaloids from fruits of Evodia rutaecarpa.

    Science.gov (United States)

    Huang, Xin; Li, Wei; Yang, Xiu-Wei

    2012-06-01

    Three new quinolone alkaloids, 1-methyl-2-[7-hydroxy-(E)-9-tridecenyl]-4(1H)-quinolone (1), 1-methyl-2-[(Z)-4-nonenyl]-4(1H)-quinolone (2), 1-methyl-2-[(1E,5Z)-1,5-undecadienyl]-4(1H)-quinolone (3) and one new natural product, 1-methyl-2-[(E)-1-undecenyl]-4(1H)-quinolone (4), were isolated from the dried and nearly ripe fruits of Evodia rutaecarpa (Juss.) Benth., along with thirteen known compounds (5-17). In addition, one new artificial product, 1-methyl-2-[7-carbonyl-(E)-9-tridecenyl]-4(1H)-quinolone (1A) was also obtained. The structures of these compounds were determined by spectroscopic analyses. The cytotoxic activities of all of the compounds against the human cancer cell lines HL-60, N-87, H-460, and Hep G(2) cells were evaluated by MTT assay. The results showed that these alkaloids inhibited cell proliferation with IC(50) values between 14μM and 22μM.

  7. Anti-cancer Lead Molecule

    KAUST Repository

    Sagar, Sunil

    2014-04-17

    Derivatives of plumbagin can be selectively cytotoxic to breast cancer cells. Derivative `A` (Acetyl Plumbagin) has emerged as a lead molecule for testing against estrogen positive breast cancer and has shown low hepatotoxicity as well as overall lower toxicity in nude mice model. The toxicity of derivative `A` was determined to be even lower than vehicle control (ALT and AST markers). The possible mechanism of action identified based on the microarray experiments and pathway mapping shows that derivative `A` could be acting by altering the cholesterol-related mechanisms. The low toxicity profile of derivative `A` highlights its possible role\\'as future anti-cancer drug and/or as an adjuvant drug to reduce the toxicity of highly toxic chemotherapeutic\\'drugs

  8. Synthesis of novel trifluoromethyl substituted furo[2,3-b]pyridine and pyrido[3',2':4,5]furo[3,2-d]pyrimidine derivatives as potential anticancer agents.

    Science.gov (United States)

    Naresh Kumar, Royya; Poornachandra, Yedla; Nagender, Punna; Mallareddy, Gannarapu; Ravi Kumar, Nagiri; Ranjithreddy, Palreddy; Ganesh Kumar, Chityal; Narsaiah, Banda

    2016-01-27

    A series of novel trifluoromethyl substituted furo[2,3-b]pyridine and pyrido[3',2':4,5]furo[3,2-d] pyrimidine derivatives 3a-b, 6a-k, 9, 10a-b, 11a-c and 12a-c were prepared from 2-carbethoxy-3-amino-6-trifluoromethyl furo[2,3-b]pyridine 1 under different set of conditions. Compounds functionalized with oxadiazole 11a-c were also prepared from 2-carbohydrazide-3-amino-6-trifluoromethyl furo[2,3-b]pyridine 4. All the final products were screened for anticancer activity against four human cancer cell lines such as Neuro-2a, Hela, A549 and COLO 205 as well as normal human lung cell line, IMR-90. All the compounds showed promising anticancer activity against all the tested cell lines at <25 μM concentration except 5b, 6d, 6e and 6k. The selectivity index (SI) values have also been calculated for all the tested compounds in comparison to the normal cell line. Compounds 6g, 10a, 10b, and 11a were considered as potential leads which showed cytotoxicity with IC50 values of 10, 10.7, 11.0 and 10.5 μM, respectively. Compounds 7 and 12a were considered as highly potent exhibiting promising cytotoxicity with IC50 value of 5.8 and 3.6 μM, respectively.

  9. Comparison of the electronic properties, and thermodynamic and kinetic parameters of the aquation of selected platinum(II) derivatives with their anticancer IC50 indexes.

    Science.gov (United States)

    Bradác, Ondrej; Zimmermann, Tomás; Burda, Jaroslav V

    2008-08-01

    Three potential anticancer agents {trans-[PtCl(2)(NH(3))(thiazole)], cis-[PtCl(2)(NH(3))(piperidine)], and PtCl(2)(NH(3))(cyclohexylamine) (JM118)} were explored and compared with cisplatin and the inactive [PtCl(dien)](+) complex. Basic electronic properties, bonding and stabilization energies were determined, and thermodynamic and kinetic parameters for the aquation reaction were estimated at the B3LYP/6-311++G(2df,2pd) level of theory. Since the aquation process represents activation of these agents, the obtained rate constants were compared with the experimental IC(50) values for several tumor cells. Despite the fact that the processes in which these drugs are involved and the way in which they affect cells are very complex, some correlations can be deduced.

  10. Nitroimidazoles, Quinolones and Oxazolidinones as Fluorine Bearing Antitubercular Clinical Candidates.

    Science.gov (United States)

    Patel, Rahul V; Keum, Young-Soo; Park, Se Won

    2015-01-01

    Tuberculosis is a leading killer of lives worldwide and the global curse of multi-drug resistant tuberculosis is attaining really dangerous levels. Synergistic interaction of HIV and TB is the twin epidemics in resource-limited countries as each potentiate progression of the other. The increasing emergence of MDR-TB and XDR-TB place an immense burden for the treatment of TB with currently available drugs. The situation urgently demands for the discovery of new drugs with novel mode of action and differs in structural features in order to overcome resistance appears in conventional TB therapeutics. The present report covers the discovery of three classes of antituberculosis drugs, Nitroimidazoles, Quinolones and Oxazolidinones, undergoing clinical development with fluorine atom in their structures. Highly electronegative fluorine atom plays a signature role in advancing medicinal innovations as it existence in the drug compounds critically influences metabolic stability and lipophilicity thereby delaying its elimination by the body which results into a long term in vivo efficiency of the drug. Presence of fluorine atom(s) in the drug structures described in this report, has been associated with the several fold increase in the overall potency of the compound as demonstrated since the early discoveries. 6 Fluorinated derivatives from these three classes as pretomanid, delamanid, moxifloxacin, gatifloxacin, linezolid and sutezolid have been discussed with their antituberculosis effects, mode of action, chemical synthetic routes and results of clinical studies.

  11. Quinolones: review of psychiatric and neurological adverse reactions.

    Science.gov (United States)

    Tomé, Ana M; Filipe, Augusto

    2011-06-01

    Quinolones are a class of antibacterial agents for the treatment of several infectious diseases (e.g. urinary and respiratory tract infections). They are used worldwide due to their broad spectrum of activity, high bioavailability and good safety profile. The safety profile varies from quinolone to quinolone. The aim of this article was to review the neurological and psychiatric adverse drug reaction (ADR) profile of quinolones, using a literature search strategy designed to identify case reports and case series. A literature search using PubMed/MEDLINE (from inception to 31 October 2010) was performed to identify case reports and case series related to quinolone-associated neurological and psychiatric ADRs. The search was conducted in two phases: the first phase was the literature search and in the second phase relevant articles were identified through review of the references of the selected articles. Relevant articles were defined as articles referring to adverse events/reactions associated with the use of any quinolone. Abstracts referring to animal studies, clinical trials and observational studies were excluded. Identified case reports were analysed by age group, sex, active substances, dosage, concomitant medication, ambulatory or hospital-based event and seriousness, after Medical Dictionary for Regulatory Activities (MedDRA®) coding. From a total of 828 articles, 83 were identified as referring to nervous system and/or psychiatric disorders induced by quinolones. 145 individual case reports were extracted from the 83 articles. 40.7% of the individual case reports belonged to psychiatric disorders only, whereas 46.9% related to neurological disorders only. Eight (5.5%) individual case reports presented both neurological and psychiatric ADRs. Ciprofloxacin, ofloxacin and pefloxacin were the quinolones with more neurological and psychiatric ADRs reported in the literature. Ciprofloxacin has been extensively used worldwide, which may explain the higher number

  12. Synthesis of Novel 1-Substituted and 1,9-Disubstituted-1,2,3,4-tetrahydro-9H-Carbazole Derivatives as Potential Anticancer Agents

    Directory of Open Access Journals (Sweden)

    H. I. El-Diwani

    2000-10-01

    Full Text Available Condensation of 1-acetyl-1,2,3,4-tetrahydro-9H-carbazole (2 with some amino compounds furnished the corresponding imino derivatives 3a-e. Compound 3a reacted with chloroacetic acid and underwent cyclization to give the thiazolidine derivative 5. Also, treatment of 3c with thionyl chloride caused cyclization to yield the [1,2,6]thiadiazino derivative 6, which gave the corresponding N-formyl derivative 7 upon heating with ethyl formate. In addition, interaction of 3d with ethyl cyanoacetate yielded the monoamide of malonic acid derivative 8. Acylation of carbazole 1 with succinoyl chloride or phenylacetyl choride produced the corresponding azepine (11 and 1,9-diphenyl acetyl derivatives (14, respectively. Compounds 11, 14 were further reacted to give the carbazole derivatives 12, 13 and 15a,b. The cytotoxic activity for some of the prepared compounds against breast cancer B20 is discussed.

  13. QSAR study and VolSurf characterization of anti-HIV quinolone library

    Science.gov (United States)

    Filipponi, Enrica; Cruciani, Gabriele; Tabarrini, Oriana; Cecchetti, Violetta; Fravolini, Arnaldo

    2001-03-01

    Antiviral quinolones are promising compounds in the search for new therapeutically effective agents for the treatment of AIDS. To rationalize the SAR for this new interesting class of anti-HIV derivatives, we performed a 3D-QSAR study on a library of 101 6-fluoro and 6-desfluoroquinolones, taken either from the literature or synthesized by us. The chemometric procedure involved a fully semiempirical minimization of the molecular structures by the AMSOL program, which takes into account the solvatation effect, and their 3D characterization by the VolSurf/GRID program. The QSAR analysis, based on PCA and PLS methods, shows the key structural features responsible for the antiviral activity.

  14. [Sample preprocessing method for residual quinolones in honey using immunoaffinity resin].

    Science.gov (United States)

    Ihara, Yoshiharu; Kato, Mihoko; Kodaira, Tsukasa; Itoh, Shinji; Terakawa, Mika; Horie, Masakazu; Saito, Koichi; Nakazawa, Hiroyuki

    2009-06-01

    A sample preparation method was developed for determination of quinolones in honey using immunoaffinity resin. For this purpose, an immunoaffinity resin for quinolones was prepared by coupling a quinolone-specific monoclonal antibody to agarose resin. Honey samples diluted with phosphate buffer were reacted with immunoaffinity resin. After the resin was washed, quinolones were eluted with glycine-HCl. Quinolones in the eluate were determined by HPLC with fluorescence detection. No interfering peak was found on the chromatograms of honey samples. The recoveries of quinolones from samples were over 70% at fortification levels of 20 ng/g (for norfloxacin, ciprofloxacin and enrofloxacin) and 10 ng/g (for danofloxacin). The quantification limits of quinolones were 2 ng/g. This sample preprocessing method using immunoaffinity resin was found to be effective and suitable for determining residual quinolones in honey.

  15. Coordination behavior of new bis Schiff base ligand derived from 2-furan carboxaldehyde and propane-1,3-diamine. Spectroscopic, thermal, anticancer and antibacterial activity studies.

    Science.gov (United States)

    Mohamed, Gehad G; Zayed, Ehab M; Hindy, Ahmed M M

    2015-06-15

    Novel bis Schiff base ligand, [N1,N3-bis(furan-2-ylmethylene)propane-1,3-diamine], was prepared by the condensation of furan-2-carboxaldehyde with propane-1,3-diamine. Its conformational changes on complexation with transition metal ions [Co(II), Ni(II), Cu(II), Mn(II), Cd(II), Zn(II) and Fe(III)] have been studied on the basis of elemental analysis, conductivity measurements, spectral (infrared, (1)H NMR, electronic), magnetic and thermogravimetric studies. The conductance data of the complexes revealed their electrolytic nature suggesting them as 1:2 (for bivalent metal ions) and 1:3 (for Fe(III) ion) electrolytes. The complexes were found to have octahedral geometry based on magnetic moment and solid reflectance measurements. Thermal analysis data revealed the decomposition of the complexes in successive steps with the removal of anions, coordinated water and bis Schiff base ligand. The thermodynamic parameters were calculated using Coats-Redfern equation. The Anticancer screening studies were performed on human colorectal cancer (HCT), hepatic cancer (HepG2) and breast cancer (MCF-7) cell lines. The antimicrobial activity of all the compounds was studied against Gram negative (Escherichia coli and Proteus vulgaris) and Gram positive (Bacillus vulgaris and Staphylococcus pyogones) bacteria. It was observed that the coordination of metal ion has a pronounced effect on the microbial activities of the bis Schiff base ligand. All the metal complexes have shown higher antimicrobial effect than the free bis Schiff base ligand.

  16. Structure Effect of Some New Anticancer Pt(II) Complexes of Amino Acid Derivatives with Small Branched or Linear Hydrocarbon Chains on Their DNA Interaction.

    Science.gov (United States)

    Kantoury, Mahshid; Eslami Moghadam, Mahboube; Tarlani, Ali Akbar; Divsalar, Adeleh

    2016-07-01

    The aim of this study was to investigate the structure effect and identify the modes of binding of amino acid-Pt complexes to DNA molecule for cancer treatment. Hence, three novel water soluble platinum complexes, [Pt(phen)(R-gly)]NO3 (where phen is 1,10-phenanthroline, R-gly is methyl, amyl, and isopentyl-glycine), have been synthesized and characterized by spectroscopic methods, conductivity measurements, and chemical analysis. The anticancer activities of synthesized complexes were investigated against human breast cancer cell line of MDA-MB 231. The 50% cytotoxic concentration values were determined to be 42.5, 58, and 70 μm for methyl-, amyl-, and isopentyl-gly complexes, respectively. These complexes were interacted with calf thymus DNA (ct-DNA) via positive cooperative interaction. The modes of binding of the complexes to DNA were investigated by fluorescence spectroscopy and circular dichroism in combination with a molecular docking study. The result indicates that complexes with small or branched hydrocarbon chains can intercalate with DNA. This is while amyl complexes with linear chains interacted additionally via groove binding. The results of the negative value of Gibbs energy for binding of isopentyl-platinum to DNA and those of the molecular docking were coherent. Furthermore, the docking results demonstrated that hydrophobic interaction plays an important role in the complex-DNA interaction.

  17. In Silico Models for Designing and Discovering Novel Anticancer Peptides

    Science.gov (United States)

    Tyagi, Atul; Kapoor, Pallavi; Kumar, Rahul; Chaudhary, Kumardeep; Gautam, Ankur; Raghava, G. P. S.

    2013-10-01

    Use of therapeutic peptides in cancer therapy has been receiving considerable attention in the recent years. Present study describes the development of computational models for predicting and discovering novel anticancer peptides. Preliminary analysis revealed that Cys, Gly, Ile, Lys, and Trp are dominated at various positions in anticancer peptides. Support vector machine models were developed using amino acid composition and binary profiles as input features on main dataset that contains experimentally validated anticancer peptides and random peptides derived from SwissProt database. In addition, models were developed on alternate dataset that contains antimicrobial peptides instead of random peptides. Binary profiles-based model achieved maximum accuracy 91.44% with MCC 0.83. We have developed a webserver, which would be helpful in: (i) predicting minimum mutations required for improving anticancer potency; (ii) virtual screening of peptides for discovering novel anticancer peptides, and (iii) scanning natural proteins for identification of anticancer peptides (http://crdd.osdd.net/raghava/anticp/).

  18. Discovery of diethyl 2,5-diaminothiophene-3,4-dicarboxylate derivatives as potent anticancer and antimicrobial agents and screening of anti-diabetic activity: synthesis and in vitro biological evaluation. Part 1.

    Science.gov (United States)

    Bozorov, Khurshed; Ma, Hai-Rong; Zhao, Jiang-Yu; Zhao, Hai-Qing; Chen, Hua; Bobakulov, Khayrulla; Xin, Xue-Lei; Elmuradov, Burkhon; Shakhidoyatov, Khusnutdin; Aisa, Haji A

    2014-09-12

    Series of diethyl 2,5-diaminothiophene-3,4-dicarboxylate (DDTD) derivatives: azomethines of DDTD (2a-l) have been synthesized and screened for their anticancer, antimicrobial and anti-diabetic activities. The novel synthesized compounds were characterized by (1)H, (13)C NMR, MS and FT-IR analyses. All compounds were evaluated for their antiproliferative activity against three types of cancer cell line such as T47D and MCF-7 (human breast cancer), Hela (human cervical cancer) and Ishikawa (human endometrial cancer) lines. The results showed that most compounds exhibited significant antiproliferative activity against breast cancer cells. The majority of azomethines DDTD influenced strongly against breast cancer cells T47D and MCF-7, among them compounds 2b (2.3 μM), 2c (12.1 μM), 2e (13.2 μM), 2i (14.9 μM), 2j (16.0 μM), 2k (7.1 μM), 2l (8.6 μM) manifest potent anticancer activity against cancer cell T47D than Doxorubicin (DOX, 15.5 μM). Compound 2j has shown potent activity on all three types of cancer cells concurrently and IC50 values were considerably low in comparison with positive control DOX. In addition, all compounds were tested for antimicrobial activity against Staphylococcus aureus ATCC 6538 (Gram positive bacteria), Escherichia coli ATCC 11229 (Gram negative bacteria) and Candida albicans ATCC 10231 (Fungi) strains and 2j which contains in the ring nitrofurfural fragment, showed the highest effect on the three species of microbial pathogens simultaneously. Some compounds induced enzymatic inhibition in a concentration-dependent manner on PTP-1B inhibitor.

  19. Design, Synthesis, Molecular Docking, and Antibacterial Evaluation of Some Novel Flouroquinolone Derivatives as Potent Antibacterial Agent

    Directory of Open Access Journals (Sweden)

    Mehul M. Patel

    2014-01-01

    Full Text Available Objective. Quinolone moiety is an important class of nitrogen containing heterocycles widely used as key building blocks for medicinal agents. It exhibits a wide spectrum of pharmacophores and has bactericidal, antiviral, antimalarial, and anticancer activities. In view of the reported antimicrobial activity of various fluoroquinolones, the importance of the C-7 substituents is that they exhibit potent antimicrobial activities. Our objective was to synthesize newer quinolone analogues with increasing bulk at C-7 position of the main 6-fluoroquinolone scaffold to produce the target compounds which have potent antimicrobial activity. Methods. A novel series of 1-ethyl-6-fluoro-4-oxo-7-{4-[2-(4-substituted phenyl-2-(substituted-ethyl]-1-piperazinyl}-1,4-dihydroquinoline-3-carboxylic acid derivatives were synthesized. To understand the interaction of binding sites with bacterial protein receptor, the docking study was performed using topoisomerase II DNA gyrase enzymes (PDB ID: 2XCT by Schrodinger’s Maestro program. In vitro antibacterial activity of the synthesized compounds was studied and the MIC value was calculated by the broth dilution method. Results. Among all the synthesized compounds, some compounds showed potent antimicrobial activity. The compound 8g exhibited good antibacterial activity. Conclusion. This investigation identified the potent antibacterial agents against certain infections.

  20. Switching electrical conductivity in an AOT-isooctane-water microemulsion through photodimerization of solubilized N-methyl-2-quinolone.

    Science.gov (United States)

    Bufe, Markus; Wolff, Thomas

    2006-09-28

    The electrical conductivity of microemulsions composed of Aerosol OT (AOT), isooctane and water as a function of temperature was studied in the absence and presence of N-methyl-2-quinolone (NMQ), and consequences of an in situ photodimerization of NMQ were investigated. A conductivity increase upon raising the temperature of a water-in-oil microemulsion indicates percolation. Percolation temperatures (Tp) can be influenced specifically by the addition of certain substances. Small amounts of solubilized N-methyl-2-quinolone induce lower Tp (by up to 9 K), and photodimerization of NMQ shifts Tp back to higher values. Consequently, the microemulsion can be switched from conducting to non-conducting without varying temperature or composition by exposing samples to UV light at lambda > 310 nm. The effect can be reverted in part by irradiation at lambda = 250 nm. Coumarin derivatives--structurally related to NMQ--show much slighter effects.

  1. Prevalence and characterisation of quinolone resistance mechanisms in Salmonella spp.

    Science.gov (United States)

    Wasyl, Dariusz; Hoszowski, Andrzej; Zając, Magdalena

    2014-07-16

    The study was focused on characterisation of quinolone resistance mechanisms in Salmonella isolated from animals, food, and feed between 2008 and 2011. Testing of Minimal Inhibitory Concentrations revealed 6.4% of 2680 isolates conferring ciprofloxacin resistance. Simultaneously 37.7% and 40.8% were accounted for, respectively, nalidixic acid and ciprofloxacin Non Wild-Type populations. Amplification and sequencing of quinolone resistance determining region of topoisomerases genes in 44 isolates identified multiple amino-acid substitutions in gyrA at positions Ser83 (N=22; → Leu, → Phe, → Tyr), Asp87 (N=22; → Asn, → Gly, → Tyr) and parC (Thr57Ser, N=23; Ala141Ser, N=1). No relevant mutations were identified in gyrB and parE. Twelve patterns combining one or two substitutions were related to neither serovar nor ciprofloxacin MIC. In 92 isolates suspected for plasmid mediated quinolone resistance two qnr alleles were found: qnrS1 (or qnrS3; N=50) and qnrB19 (or qnrB10; N=24). Additionally, two isolates with chromosomally encoded mechanisms carried qnrS1 and qnrS2. All tested isolates were negative for qnrA, qnrC, qnrD, qepA, aac(6')-Ib-cr. Both chromosomal and plasmid mediated quinolone resistance determinants were found in several Salmonella serovars and Pulsed Field Gel Electrophoresis was used to assess phylogenetic similarity of selected isolates (N=82). Salmonella Newport was found to accumulate quinolone resistance determinants and the serovar was spreading clonally with either variable gyrA mutations, qnrS1/S3, or qnrB10/B19. Alternatively, various determinants are dispersed among related S. Enteritidis isolates. Antimicrobial selection pressure, multiple resistance determinants and scenarios for their acquisition and spread make extremely difficult to combat quinolone resistance.

  2. The regioselective iodination of quinolines, quinolones, pyridones, pyridines and uracil.

    Science.gov (United States)

    Dutta, Uttam; Deb, Arghya; Lupton, David W; Maiti, Debabrata

    2015-12-28

    A radical based direct C-H iodination protocol for quinolines, quinolones, pyridones, pyridines, and uracil has been developed. The iodination occurs in a C3 selective manner for quinolines and quinolones. Pyridones and pyridines undergo C3 and C5 iodination, while dimethyl uracil undergoes C5 iodination. Scope of the method was demonstrated through the rapid synthesis of both electron rich as well as electron poor heteroaromatic iodides. The protocol was found to be scalable and general, while a mechanism has been proposed.

  3. Acute toxicity evaluation for quinolone antibiotics and their chlorination disinfection processes.

    Science.gov (United States)

    Li, Min; Wei, Dongbin; Du, Yuguo

    2014-09-01

    Acute toxicity of 21 quinolone antibiotics was monitored using photobacterium Vibrio fischeri assay. The minimum IC20 (inhibitory concentration for 20% luminescence elimination) was obtained at the least 18.86μmol/L for the tested quinolones. A quantitative structure-activity relationship model was established to investigate the possible mechanism for the acute toxicity. The critical physicochemical descriptors, describing σ and π atom electronegativity, implied that the electron transfer might occur between the quinolones and photobacterium V. fischeri. Although the quinolones exhibited limited acute toxicity to photobacterium, toxicity elevation was detected after their chlorination. Hence, chlorination disinfection treatment of quinolone-containing water should be of concerns.

  4. Genome-based Characterization of Two Prenylation Steps in the Assembly of the Stephacidin and Notoamide Anticancer Agents in a Marine-derived Aspergillus sp

    OpenAIRE

    Ding, Yousong; de Wet, Jeffrey R.; Cavalcoli, James; Li, Shengying; Greshock, Thomas J.; Miller, Kenneth A.; Finefield, Jennifer M.; Sunderhaus, James D.; McAfoos, Timothy; Tsukamoto, Sachiko; Williams, Robert M.; Sherman, David H.

    2010-01-01

    Stephacidin and notoamide natural products belong to a group of prenylated indole alkaloids containing a core bicyclo[2.2.2]diazaoctane ring system. These bioactive fungal secondary metabolites have a range of unusual structural and stereochemical features but their biosynthesis has remained uncharacterized. Herein, we report the first biosynthetic gene cluster for this class of fungal alkaloids based on whole genome sequencing of a marine-derived Aspergillus sp. Two central pathway enzymes c...

  5. Exploiting Natural Products to Build Metalla-Assemblies: The Anticancer Activity of Embelin-Derived Rh(III and Ir(III Metalla-Rectangles

    Directory of Open Access Journals (Sweden)

    Gajendra Gupta

    2014-05-01

    Full Text Available Six new pentamethylcyclopentadienyl Rh(III and Ir(III metalla-rectangles ([3](CF3SO34–[8](CF3SO34 have been prepared by a self-assembly strategy using the embelin-derived metalla-clips (η5-C5Me52M2(μ4-C6HRO4-κOCl2 (M = Rh, 1; M = Ir, 2; R = (CH210CH3 and the linear ditopic ligands, pyrazine, 4,4'-bipyridine and 1,2-bis (4-pyridylethylene. These new metalla-rectangles have been obtained in high yield and isolated as their triflate salts. The complexes have been fully characterized by standard spectroscopic techniques and the antiproliferative activity of these tetranuclear complexes was evaluated in vitro on cancerous (DU-145, A-549, HeLa and noncancerous (HEK-293 cell lines. The biological study has showed a better activity for the rhodium derivatives over the iridium analogs and for all complexes a very good selectivity for cancerous over noncancerous cells. The presence of lipophilic side chains coupled with the positive charge of the tetranuclear complexes suggested a cytotoxic activity involving the mitochondrial machinery, as demonstrated by multiple biological experiments.

  6. Synthesis and spectral characterization of Schiff base complexes of Cu(II), Co(II), Zn(II) and VO(IV) containing 4-(4-aminophenyl)morpholine derivatives: antimicrobial evaluation and anticancer studies.

    Science.gov (United States)

    Dhahagani, K; Mathan Kumar, S; Chakkaravarthi, G; Anitha, K; Rajesh, J; Ramu, A; Rajagopal, G

    2014-01-03

    Metal(II) chelates of Schiff bases derived from the condensation of 4-morpholinoaniline with substituted salicylaldehyde have been prepared and characterized by (1)H NMR, IR, electronic, EPR, and magnetic measurement studies. The complexes are of the type M(X-MPMP)2 [where M=Cu(II), Co(II)), Zn(II), or VO(IV); MPMP=2-[(4 morpholinophenyl imino) methyl] 4-X-phenol, X=Cl, (L1H), X=Br (L2H)]. Single crystal X-ray crystallography studies confirm the structure of newly synthesized Schiff bases. The Schiff bases act as bidentate monobasic ligands, coordinating through deprotonated phenolic oxygen and azomethine nitrogen atoms. The free ligands and metal complexes are screened for their biopotency. Metal complexes exhibit better activity than ligands. Anticancer activity of ligands and their metal complexes are evaluated in human heptocarcinoma(HepG2) cells. The preliminary bioassay indicates that the Schiff base and its zinc complex exhibit inhibitory activity against the human gastric cancer cell lines.

  7. Anticancer activity of fungal taxol derived from Botryodiplodia theobromae Pat., an endophytic fungus, against 7, 12 dimethyl benz(a)anthracene (DMBA)-induced mammary gland carcinogenesis in Sprague Dawley rats.

    Science.gov (United States)

    Pandi, M; Manikandan, R; Muthumary, J

    2010-01-01

    Breast cancer is the second most prevalent cancer worldwide and their incidence increases gradually. Taxol (paclitaxel), a potent anticancer drug, is naturally isolated from the bark of the Pacific yew. Taxol is widely used in the treatment of ovarian, lung and breast cancer. The increased demand for taxol, coupled with its limited availability from the protected Pacific yew, has had researchers scrambling for alternate sources. The purpose of the present study is to investigate chemopreventive effect of fungal taxol derived from a novel endophytic fungus Botryodiplodia theobromae Pat., isolated from a medicinal plant Morinda citrifolia Linn. The fungal taxol is found to be active against the 7, 12 dimethyl benz(a)anthracene (DMBA)-induced mammary gland carcinogenesis in Sprague dawley rats. The enzymic and non-enzymic antioxidants i.e. superoxide dismutase (SOD), catalase (CAT), glutatione peroxidase (GPx), glutatione-S-transferase (GST), reduced glutathione (GSH), vitamin C and vitamin E were evaluated in control and experimental groups. Lipid peroxides levels (LPO) were also tested. Histological analysis of breast tissue was analyzed by haematoxylin and eosin staining to assess the cytoprotective role of fungal taxol active against breast cancer. Immunohistochemical analyses were also performed to evaluate the effect of fungal taxol on the inflammatory marker such as Cyclooxygenase-2 (COX-2) in control and experimental groups. The results showed that the fungal taxol significantly suppresses the DMBA-induced breast cancer in Sprague dawley rats.

  8. SKLB-163, a new benzothiazole-2-thiol derivative, exhibits potent anticancer activity by affecting RhoGDI/JNK-1 signaling pathway.

    Science.gov (United States)

    Peng, X; Xie, G; Wang, Z; Lin, H; Zhou, T; Xiang, P; Jiang, Y; Yang, S; Wei, Y; Yu, L; Zhao, Y

    2014-03-27

    Small-molecule inhibitors are an attractive therapeutic approach for most types of human cancers. SKLB-163, a novel benzothiazole-2-thiol derivative, was developed via computer-aided drug design and de novo synthesis. MTT assay showed it had potent anti-proliferative activity on various human cancer cells. Treatment of cancer cells with SKLB-163 induced obvious apoptosis and inhibited proliferation in vitro. SKLB-163 administered p.o. showed a marked antitumor activity in vivo. Proteomic techniques were employed to identify possible drug target proteins. The data showed molecular mechanism of action might be involved in downregulation of RhoGDI, which finally contributed to increased apoptosis and inhibited proliferation. These findings provided the potential value of SKLB-163 as a novel candidate antitumor drug.

  9. Genome-based characterization of two prenylation steps in the assembly of the stephacidin and notoamide anticancer agents in a marine-derived Aspergillus sp.

    Science.gov (United States)

    Ding, Yousong; de Wet, Jeffrey R; Cavalcoli, James; Li, Shengying; Greshock, Thomas J; Miller, Kenneth A; Finefield, Jennifer M; Sunderhaus, James D; McAfoos, Timothy J; Tsukamoto, Sachiko; Williams, Robert M; Sherman, David H

    2010-09-15

    Stephacidin and notoamide natural products belong to a group of prenylated indole alkaloids containing a core bicyclo[2.2.2]diazaoctane ring system. These bioactive fungal secondary metabolites have a range of unusual structural and stereochemical features but their biosynthesis has remained uncharacterized. Herein, we report the first biosynthetic gene cluster for this class of fungal alkaloids based on whole genome sequencing of a marine-derived Aspergillus sp. Two central pathway enzymes catalyzing both normal and reverse prenyltransfer reactions were characterized in detail. Our results establish the early steps for creation of the prenylated indole alkaloid structure and suggest a scheme for the biosynthesis of stephacidin and notoamide metabolites. The work provides the first genetic and biochemical insights for understanding the structural diversity of this important family of fungal alkaloids.

  10. Drug interactions with Bacillus anthracis topoisomerase IV: biochemical basis for quinolone action and resistance.

    Science.gov (United States)

    Aldred, Katie J; McPherson, Sylvia A; Wang, Pengfei; Kerns, Robert J; Graves, David E; Turnbough, Charles L; Osheroff, Neil

    2012-01-10

    Bacillus anthracis, the causative agent of anthrax, is considered a serious threat as a bioweapon. The drugs most commonly used to treat anthrax are quinolones, which act by increasing the levels of DNA cleavage mediated by topoisomerase IV and gyrase. Quinolone resistance most often is associated with specific serine mutations in these enzymes. Therefore, to determine the basis for quinolone action and resistance, we characterized wild-type B. anthracis topoisomerase IV, the GrlA(S81F) and GrlA(S81Y) quinolone-resistant mutants, and the effects of quinolones and a related quinazolinedione on these enzymes. Ser81 is believed to anchor a water-Mg(2+) bridge that coordinates quinolones to the enzyme through the C3/C4 keto acid. Consistent with this hypothesized bridge, ciprofloxacin required increased Mg(2+) concentrations to support DNA cleavage by GrlA(S81F) topoisomerase IV. The three enzymes displayed similar catalytic activities in the absence of drugs. However, the resistance mutations decreased the affinity of topoisomerase IV for ciprofloxacin and other quinolones, diminished quinolone-induced inhibition of DNA religation, and reduced the stability of the enzyme-quinolone-DNA ternary complex. Wild-type DNA cleavage levels were generated by mutant enzymes at high quinolone concentrations, suggesting that increased drug potency could overcome resistance. 8-Methyl-quinazoline-2,4-dione, which lacks the quinolone keto acid (and presumably does not require the water-Mg(2+) bridge to mediate protein interactions), was more potent than quinolones against wild-type topoisomerase IV and was equally efficacious. Moreover, it maintained high potency and efficacy against the mutant enzymes, effectively inhibited DNA religation, and formed stable ternary complexes. Our findings provide an underlying biochemical basis for the ability of quinazolinediones to overcome clinically relevant quinolone resistance mutations in bacterial type II topoisomerases.

  11. Stuty on the Inclusion Interaction of Two Anticancer Xanthines and β-Cyclodextrin's Derivatives by Competitive UV-Vis Spectrophtometric Method%竞争光度法研究两种抗癌嘌呤类药物与β-环糊精衍生物的包合作用

    Institute of Scientific and Technical Information of China (English)

    卞伟; 朱媛; 杨芸芸; 张爱萍; 孙体健

    2009-01-01

    The competitive OV-Vis spectrophtometric method was applied to study the inclusion interaction and determine the inclusion constant of β-CD derivatives with two anticancer xanthines with phenolphthalein as a spectral probe in aqueous buffer solution (pH= 10. 38) at room temperature, determine the inclusion constants of 6-MP, BAN and β-Cyclodextrin (β-CD)'s derivatives,β-CD's derivatives can include two anticancer xanthines to form the inclusion compounds. The different inclusion stability constants of β-CD's derivatives encapsulating two anticancer xanthines were given.%利用酚酞作为光谱探针,竞争光度法研究了β-环糊精衍生物在室温下,pH=10.38的缓冲液中与硫唑嘌呤和巯嘌呤的包合性能.固定β-环糊精衍生物和酚酞的浓度,随着硫唑嘌呤和巯嘌呤两种药物浓度增大,酚酞的紫外吸收增加,表明β-环糊精衍生物与两种嘌呤类药物形成包合物并得出了包合常数.

  12. 4-(1H)-Quinolones and 1,2,3,4-Tetrahydroacridin-9(10H)-ones prevent the transmission of Plasmodium falciparum to Anopheles freeborni.

    Science.gov (United States)

    Sáenz, Fabián E; Lacrue, Alexis N; Cross, R Matthew; Maignan, Jordany R; Udenze, Kenneth O; Manetsch, Roman; Kyle, Dennis E

    2013-12-01

    Malaria kills approximately 1 million people a year, mainly in sub-Saharan Africa. Essential steps in the life cycle of the parasite are the development of gametocytes, as well as the formation of oocysts and sporozoites, in the Anopheles mosquito vector. Preventing transmission of malaria through the mosquito is necessary for the control of the disease; nevertheless, the vast majority of drugs in use act primarily against the blood stages. The study described herein focuses on the assessment of the transmission-blocking activities of potent antierythrocytic stage agents derived from the 4(1H)-quinolone scaffold. In particular, three 3-alkyl- or 3-phenyl-4(1H)-quinolones (P4Qs), one 7-(2-phenoxyethoxy)-4(1H)-quinolone (PEQ), and one 1,2,3,4-tetrahydroacridin-9(10H)-one (THA) were assessed for their transmission-blocking activity against the mosquito stages of the human malaria parasite (Plasmodium falciparum) and the rodent parasite (P. berghei). Results showed that all of the experimental compounds reduced or prevented the exflagellation of male gametocytes and, more importantly, prevented parasite transmission to the mosquito vector. Additionally, treatment with ICI 56,780 reduced the number of sporozoites that reached the Anopheles salivary glands. These findings suggest that 4(1H)-quinolones, which have activity against the blood stages, can also prevent the transmission of Plasmodium to the mosquito and, hence, are potentially important drug candidates to eradicate malaria.

  13. Anti-cancer activity of an osthole derivative, NBM-T-BMX-OS01: targeting vascular endothelial growth factor receptor signaling and angiogenesis.

    Directory of Open Access Journals (Sweden)

    Hung-Yu Yang

    Full Text Available Angiogenesis occurs during tissue growth, development and wound healing. It is also required for tumor progression and represents a rational target for therapeutic intervention. NBM-T-BMX-OS01 (BMX, derived from the semisynthesis of osthole, an active ingredient isolated from Chinese herb Cnidium monnieri (L. Cuss., was recently shown to enhance learning and memory in rats. In this study, we characterized the anti-angiogenic activities of NBM-T-BMX-OS01 (BMX in an effort to develop novel inhibitors to suppress angiogenesis and tumor growth. BMX inhibited vascular endothelial growth factor (VEGF-induced proliferation, migration and endothelial tube formation in human umbilical endothelial cells (HUVECs. BMX also attenuated VEGF-induced microvessel sprouting from aortic rings ex vivo and reduced HCT116 colorectal cancer cells-induced angiogenesis in vivo. Moreover, BMX inhibited the phosphorylation of VEGFR2, FAK, Akt and ERK in HUVECs exposed to VEGF. BMX was also shown to inhibit HCT116 cell proliferation and to suppress the growth of subcutaneous xenografts of HCT116 cells in vivo. Taken together, this study provides evidence that BMX modulates vascular endothelial cell remodeling and leads to the inhibition of tumor angiogenesis. These results also support the role of BMX as a potential drug candidate and warrant the clinical development in the treatment of cancer.

  14. Anti-cancer activity of an osthole derivative, NBM-T-BMX-OS01: targeting vascular endothelial growth factor receptor signaling and angiogenesis.

    Science.gov (United States)

    Yang, Hung-Yu; Hsu, Ya-Fen; Chiu, Pei-Ting; Ho, Shiau-Jing; Wang, Chi-Han; Chi, Chih-Chin; Huang, Yu-Han; Lee, Cheng-Feng; Li, Ying-Shiuan; Ou, George; Hsu, Ming-Jen

    2013-01-01

    Angiogenesis occurs during tissue growth, development and wound healing. It is also required for tumor progression and represents a rational target for therapeutic intervention. NBM-T-BMX-OS01 (BMX), derived from the semisynthesis of osthole, an active ingredient isolated from Chinese herb Cnidium monnieri (L.) Cuss., was recently shown to enhance learning and memory in rats. In this study, we characterized the anti-angiogenic activities of NBM-T-BMX-OS01 (BMX) in an effort to develop novel inhibitors to suppress angiogenesis and tumor growth. BMX inhibited vascular endothelial growth factor (VEGF)-induced proliferation, migration and endothelial tube formation in human umbilical endothelial cells (HUVECs). BMX also attenuated VEGF-induced microvessel sprouting from aortic rings ex vivo and reduced HCT116 colorectal cancer cells-induced angiogenesis in vivo. Moreover, BMX inhibited the phosphorylation of VEGFR2, FAK, Akt and ERK in HUVECs exposed to VEGF. BMX was also shown to inhibit HCT116 cell proliferation and to suppress the growth of subcutaneous xenografts of HCT116 cells in vivo. Taken together, this study provides evidence that BMX modulates vascular endothelial cell remodeling and leads to the inhibition of tumor angiogenesis. These results also support the role of BMX as a potential drug candidate and warrant the clinical development in the treatment of cancer.

  15. Novel 3-Amino-6-chloro-7-(azol-2 or 5-yl-1,1-dioxo-1,4,2-benzodithiazine Derivatives with Anticancer Activity: Synthesis and QSAR Study

    Directory of Open Access Journals (Sweden)

    Aneta Pogorzelska

    2015-12-01

    Full Text Available A series of new 3-amino-6-chloro-7-(azol-2 or 5-yl-1,1-dioxo-1,4,2-benzodithiazine derivatives 5a–j have been synthesized and evaluated in vitro for their antiproliferative activity at the U.S. National Cancer Institute. The most active compound 5h showed significant cytotoxic effects against ovarian (OVCAR-3 and breast (MDA-MB-468 cancer (10% and 47% cancer cell death, respectively as well as a good selectivity toward prostate (DU-145, colon (SW-620 and renal (TK-10 cancer cell lines. To obtain a deeper insight into the structure-activity relationships of the new compounds 5a–j QSAR studies have been applied. Theoretical calculations allowed the identification of molecular descriptors belonging to the RDF (RDF055p and RDF145m in the MOLT-4 and UO-31 QSAR models, respectively and 3D-MorSE (Mor32m and Mor16e for MOLT-4 and UO-31 QSAR models descriptor classes. Based on these data, QSAR models with good robustness and predictive ability have been obtained.

  16. Anti-cancer effects of 2-oxoquinoline derivatives on the HCT116 and LoVo human colon cancer cell lines.

    Science.gov (United States)

    Fang, Feng-Qi; Guo, Hui-Shu; Zhang, Jie; Ban, Li-Ying; Liu, Ji-Wei; Yu, Pei-Yao

    2015-12-01

    The present study demonstrated the anti-tumor effects of the quinoline derivative [5-(3-chloro-oxo-4-phenyl-cyclobutyl)-quinoli-8-yl-oxy] acetic acid hydrazide (CQAH) against colorectal carcinoma. Substantial apoptotic effects of CQAH on HCT116 and LoVo human colon cancer cell lines were observed. Apoptosis was identified based on cell morphological characteristics, including cell shrinkage and chromatin condensation as well as Annexin V/propidium iodide double staining followed by flow cytometric analysis and detection of apoptosis-associated proteins by western blot analysis. CQAH induced caspase-3 and PARP cleavage, reduced the expression of the anti-apoptotic proteins myeloid cell leukemia-1 and B-cell lymphoma (Bcl) extra large protein and elevated the expression of the pro-apoptotic protein Bcl-2 homologous antagonist killer. In addition, pharmacological inhibition of c-Jun N-terminal kinase (JNK), but not extracellular signal-regulated kinase or p38, significantly reduced CQAH-mediated cell death as well as cleavage of caspase-3 and PARP. Co-treatment of CQAH with the commercial chemotherapeutics 5-fluorouracil and camptothecin-11 significantly improved their efficacies. Comparison of the apoptotic effects of CQAH with those of two illustrated structure-activity associations for this compound type, indicating that substitution at position-4 of the azetidine phenyl ring is pivotal for inducing apoptosis. In conclusion, the results of the present study indicated CQAH and its analogues are potent candidate drugs for the treatment of colon carcinoma.

  17. Diospyrin derivative, an anticancer quinonoid, regulates apoptosis at endoplasmic reticulum as well as mitochondria by modulating cytosolic calcium in human breast carcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Binod [Department of Pharmaceutical Technology, Jadavpur University, Kolkata 700032 (India); Radiation and Cancer Biology Section, Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Kumar, Amit [Radiation and Cancer Biology Section, Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Ghosh, Subhalakshmi [Department of Pharmaceutical Technology, Jadavpur University, Kolkata 700032 (India); Pandey, Badri N., E-mail: bnp@barc.gov.in [Radiation and Cancer Biology Section, Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Mishra, Kaushala P. [Radiation and Cancer Biology Section, Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Hazra, Banasri, E-mail: banasrihazra@yahoo.co.in [Department of Pharmaceutical Technology, Jadavpur University, Kolkata 700032 (India)

    2012-01-13

    Highlights: Black-Right-Pointing-Pointer Diospyrin diethylether (D7) caused oxidative stress-dependent activation of PC-PLC. Black-Right-Pointing-Pointer Activated PC-PLC induced a sustained-release of Ca{sup 2+} from endoplasmic reticulum. Black-Right-Pointing-Pointer The elevated cytosolic Ca{sup +2} led to the calpain-caspase12 dependent apoptosis. Black-Right-Pointing-Pointer D7-Induced Ca{sup +2} also found to accentuate the mitochondrial pathway of apoptosis. -- Abstract: Diospyrin diethylether (D7), a bisnaphthoquinonoid derivative, exhibited an oxidative stress-dependent apoptosis in several human cancer cells and tumor models. The present study was aimed at evaluation of the increase in cytosolic calcium [Ca{sup 2+}]{sub c} leading to the apoptotic cell death triggered by D7 in MCF7 human breast carcinoma cells. A phosphotidylcholine-specific phospholipase C (PC-PLC) inhibitor, viz. U73122, and an antioxidant, viz. N-acetylcysteine, could significantly prevent the D7-induced rise in [Ca{sup 2+}]{sub c} and PC-PLC activity. Using an endoplasmic reticulum (ER)-Ca{sup 2+} mobilizer (thapsigargin) and an ER-IP3R antagonist (heparin), results revealed ER as a major source of [Ca{sup 2+}]{sub c} which led to the activation of calpain and caspase12, and cleavage of fodrin. These effects including apoptosis were significantly inhibited by the pretreatment of Bapta-AM (a cell permeable Ca{sup 2+}-specific chelator), or calpeptin (a calpain inhibitor). Furthermore, D7-induced [Ca{sup 2+}]{sub c} was found to alter mitochondrial membrane potential and induce cytochrome c release, which was inhibited by either Bapta-AM or ruthenium red (an inhibitor of mitochondrial Ca{sup 2+} uniporter). Thus, these results provided a deeper insight into the D7-induced redox signaling which eventually integrated the calcium-dependent calpain/caspase12 activation and mitochondrial alterations to accentuate the induction of apoptotic cell death.

  18. Anticancer properties of Monascus metabolites.

    Science.gov (United States)

    Yang, Tao; Liu, Junwen; Luo, Feijun; Lin, Qinlu; Rosol, Thomas J; Deng, Xiyun

    2014-08-01

    This review provides up-to-date information on the anticancer properties of Monascus-fermented products. Topics covered include clinical evidence for the anticancer potential of Monascus metabolites, bioactive Monascus components with anticancer potential, mechanisms of the anticancer effects of Monascus metabolites, and existing problems as well as future perspectives. With the advancement of related fields, the development of novel anticancer Monascus food products and/or pharmaceuticals will be possible with the ultimate goal of decreasing the incidence and mortality of malignancies in humans.

  19. Resistance to quinolones in Campylobacter jejuni and Campylobacter coli from Danish broilers at farm level

    DEFF Research Database (Denmark)

    Pedersen, Karl; Wedderkopp, A.

    2003-01-01

    Aims : To investigate the prevalence of quinolone resistance among Campylobacter jejuni and Camp. coli isolates from Danish poultry at the farm level, as well as for the whole country. Methods and Results : Data and isolates were collected from a national surveillance of Campylobacter in poultry....... Quinolone resistance was investigated by determination of minimum inhibitory concentration (MIC) to nalidixic acid and enrofloxacin. Among Camp. jejuni and Camp. coli combined, 7.5% were resistant to nalidixic acid. Quinolone resistance varied considerably from farm to farm, with 0% on some farms and almost...... 100% on others, but the resistance was evenly distributed geographically. With respect to isolates from farms where resistance was detected, quinolone resistance was higher among Camp. coli (28.7%) than among Camp. jejuni (11.3%). PFGE typing of quinolone-resistant and quinolone-susceptible isolates...

  20. Antagonism of vitamin C and vitamin E on action of quinolones

    Directory of Open Access Journals (Sweden)

    Julius E. Surdjawidjaja

    2015-12-01

    Full Text Available The quinolone antibiotics are potent drugs for combating infections caused by various bacterial species with satisfactory results and relatively minimal adverse effects. Antioxidant dietary supplements, such as vitamin C (ascorbic acid and vitamin E (a-tocopherol, are occasionally prescribed along with quinolone antibiotics during the course of treatment of an infection. Therefore it is important to understand the effects of these antioxidants on the antibacterial action of quinolone antibiotics.

  1. Recent progress in the development of anti-malarial quinolones.

    Science.gov (United States)

    Beteck, Richard M; Smit, Frans J; Haynes, Richard K; N'Da, David D

    2014-08-30

    Available anti-malarial tools have over the ten-year period prior to 2012 dramatically reduced the number of fatalities due to malaria from one million to less than six-hundred and thirty thousand. Although fewer people now die from malaria, emerging resistance to the first-line anti-malarial drugs, namely artemisinins in combination with quinolines and arylmethanols, necessitates the urgent development of new anti-malarial drugs to curb the disease. The quinolones are a promising class of compounds, with some demonstrating potent in vitro activity against the malaria parasite. This review summarizes the progress made in the development of potential anti-malarial quinolones since 2008. The efficacy of these compounds against both asexual blood stages and other stages of the malaria parasite, the nature of putative targets, and a comparison of these properties with anti-malarial drugs currently in clinical use, are discussed.

  2. Engineer Novel Anticancer Bioagents

    Science.gov (United States)

    2010-10-01

    selection (hence to create marker-free genetically modified organism – GMO as required by FDA regulations) have failed. The overall transformation...free genetically modified organism – GMO , as required by FDA regulations). Key Research Status 1. Reconstitution of a complete FK228 biosynthetic...5 Food and Drug Administration (FDA) as a new class of anticancer drug for the treatment of 1 cutaneous T-cell lymphoma (CTCL) (1). FK228

  3. Quinolone-based drugs against Toxoplasma gondii and Plasmodium spp.

    Science.gov (United States)

    Anquetin, Guillaume; Greiner, Jacques; Vierling, Pierre

    2005-09-01

    Owing to the rapid emergence of multi-resistant strains of Plasmodium spp. (the causative agents of malaria) and the limitations of drugs used against Toxoplasma gondii (an important opportunistic pathogen associated with AIDS and congenital birth defects), the discovery of new therapeutical targets and the development of new drugs are needed. The presence of the prokaryotic-like organelle in apicomplexan parasites (i.e. plastids), which comprise these major human pathogens, may represent a unique target for antibiotics against these protozoa. Quinolones which are known to be highly potent against bacteria were also found to specifically disrupt these parasites. They inhibit DNA replication by interacting with two essential bacterial type II topoisomerases, DNA gyrase and topoisomerase IV. There are some clues that quinolones act on plastids with a similar mechanism of action. After a brief presentation of plasmodium and toxoplasma dedicated to their life cycle, the chemotherapies presently used in clinics to fight against these protozoa and the potential new targets and drugs, we will focus our attention on their plastid which is one of these promising new targets. Then, we will present the various drugs and generations of quinolones, the leading molecules, and their inhibitory effects against these parasites together with their pharmacological properties that have been established from in vitro and in vivo studies. We will also discuss their possible mode of action.

  4. Synthesis and biological evaluation of novel hybrid matrine derivatives as anticancer agents%新型苦参碱衍生物杂合体的合成及抗肿瘤活性

    Institute of Scientific and Technical Information of China (English)

    何黎琴; 杨琦; 顾宏霞; 张奕华; 王效山

    2012-01-01

    Matrine,one of the major active alkaloids isolated from the Sophora alopecuroides L which is a useful Chinese herbal drug, possesses antipyretic, anti-inflammatory, analgesic and notable antiviral activities , and has been used for the treatment of lipopolysaccharide-induced liver injury. Recently, it bas been reported that matrine could inhibit the growth of tumor cells. Nitric oxide(NO) ,a free radical molecule,is involved in numerous physiological and pathological processes, with high levels NO usually are toxic to tumor cells. It was therefore of interest to determine whether the hybrid of matrine and NO donor furoxan would provide a hitherto unknown class of matrine derivatives that possess potent anticancer activity. Herein 14 hybrid matrine derivatives conjugated with nitric oxide (NO) donor were designed and synthesized based on molecular hybridization strategy. All target compounds were evaluated for anti-proliferative activity against human hepatocellular HepG2 cells in vitro by MTT method. The results indicated that all of these compounds had potent anti-proliferative activity which were more potent than their parent compounds.%目的 为进一步提高苦参碱的抗肿瘤活性,基于分子杂合策略,设计合成N-苄基苦参酸一氧化氮杂合体衍生物,并对其体外抗肿瘤活性进行初步研究.方法 将NO供体硝酸酯通过连接基团与N-苄基苦参酸的羧基连接制得NO供体型N-苄基苦参酸衍生物.采用MTT法测定了目标化合物对人肝癌细胞(HepG2)增殖的体外抑制活性.结果与结论 合成了14个结构新颖的N-苄基苦参酸一氧化氮杂合体衍生物,其结构经MS、IR、1H-NMR确证,且目标化合物均具有较苦参碱强的增殖抑制活性.

  5. Prevalence and characteristics of quinolone resistance in Escherichia coli in veal calves.

    Science.gov (United States)

    Hordijk, Joost; Veldman, Kees; Dierikx, Cindy; van Essen-Zandbergen, Alieda; Wagenaar, Jaap A; Mevius, Dik

    2012-04-23

    Quinolone resistance is studied and reported increasingly in isolates from humans, food-producing animals and companion animals. Resistance can be caused by chromosomal mutations in topoisomerase genes, plasmid-mediated resistance genes, and active transport through efflux pumps. Cross sectional data on quinolone resistance mechanisms in non-pathogenic bacteria from healthy veal calves is limited. The purpose of this study was to determine the prevalence and characteristics of quinolone resistance mechanisms in Escherichia coli isolates from veal calves, after more than 20 years of quinolone usage in veal calves. MIC values were determined for all isolates collected as part of a national surveillance program on antimicrobial resistance in commensal bacteria in food-producing animals in The Netherlands. From the strains collected from veal calves in 2007 (n=175) all isolates with ciprofloxacin MIC ≥ 0.125 mg/L (n=25) were selected for this study, and screened for the presence of known quinolone resistance determinants. In this selection only chromosomal mutations in the topoisomerase type II and IV genes were detected. The number of mutations found per isolate correlated with an increasing ciprofloxacin MIC. No plasmid-mediated quinolone resistance genes were found. The contribution of efflux pumps varied from no contribution to a 16-fold increase in susceptibility. No correlation was found with the presence of resistance genes of other antimicrobial classes, even though all quinolone non-wild type isolates were resistant to 3 or more classes of antibiotics other than quinolones. Over twenty years of quinolone usage in veal calves in The Netherlands did not result in a widespread occurrence of plasmid-mediated quinolone resistance, limiting the transmission of quinolone resistance to clonal distribution.

  6. Characterization of Campylobacter jejuni DNA gyrase as the target of quinolones.

    Science.gov (United States)

    Changkwanyeun, Ruchirada; Usui, Masaru; Kongsoi, Siriporn; Yokoyama, Kazumasa; Kim, Hyun; Suthienkul, Orasa; Changkaew, Kanjana; Nakajima, Chie; Tamura, Yutaka; Suzuki, Yasuhiko

    2015-08-01

    Quinolones have long been used as the first-line treatment for Campylobacter infections. However, an increased resistance to quinolones has raised public health concerns. The development of new quinolone-based antibiotics with high activity is critical for effective, as DNA gyrase, the target of quinolones, is an essential enzyme for bacterial growth in several mechanisms. The evaluation of antibiotic activity against Campylobacter jejuni largely relies on drug susceptibility tests, which require at least 2 days to produce results. Thus, an in vitro method for studying the activity of quinolones against the C. jejuni DNA gyrase is preferred. To identify potent quinolones, we investigated the interaction of C. jejuni DNA gyrase with a number of quinolones using recombinant subunits. The combination of purified subunits exhibited DNA supercoiling activity in an ATP dependent manner. Drug concentrations that inhibit DNA supercoiling by 50% (IC50s) of 10 different quinolones were estimated to range from 0.4 (sitafloxacin) to >100 μg/mL (nalidixic acid). Sitafloxacin showed the highest inhibitory activity, and the analysis of the quinolone structure-activity relationship demonstrated that a fluorine atom at R-6 might play the important role in the inhibitory activity against C. jejuni gyrase. Measured quinolone IC50s correlated well with minimum inhibitory concentrations (R = 0.9943). These suggest that the in vitro supercoiling inhibition assay on purified recombinant C. jejuni DNA gyrase is a useful and predictive technique to monitor the antibacterial potency of quinolones. And furthermore, these data suggested that sitafloxacin might be a good candidate for clinical trials on campylobacteriosis.

  7. Contribution of topoisomerase IV mutation to quinolone resistance in Mycoplasma genitalium.

    Science.gov (United States)

    Yamaguchi, Yuko; Takei, Masaya; Kishii, Ryuta; Yasuda, Mitsuru; Deguchi, Takashi

    2013-04-01

    The mechanism of quinolone resistance in Mycoplasma genitalium remains poorly understood due to difficulties with in vitro culture, especially of clinical isolates. In this study, to confirm the association between mutations in topoisomerases and antimicrobial susceptibilities to quinolones, ciprofloxacin-resistant mutant strains were selected using the cultivable type strain ATCC 33530. Sequence analysis revealed that the mutant strains harbored mutations in topoisomerase IV: Gly81Cys in ParC, Pro261Thr in ParC, or Asn466Lys in ParE. The MICs of all quinolones tested against the mutant strains were 2- to 16-fold higher than those against the wild-type strain. No cross-resistance was observed with macrolides or tetracyclines. We determined the inhibitory activities of quinolones against DNA gyrase and topoisomerase IV in order to investigate the correlation between antimicrobial susceptibility and inhibitory activity against the target enzymes, considered the primary targets of quinolones. Furthermore, using enzymatic analysis, we confirmed that Gly81Cys in the ParC quinolone resistance-determining region (QRDR) contributed to quinolone resistance. This is the first study to isolate quinolone-resistant mutant strains of M. genitalium harboring substitutions in the parC or parE gene in vitro and to measure the inhibitory activities against the purified topoisomerases of M. genitalium.

  8. Impact of mutations in DNA gyrase genes on quinolone resistance in Campylobacter jejuni.

    Science.gov (United States)

    Changkwanyeun, Ruchirada; Yamaguchi, Tomoyuki; Kongsoi, Siriporn; Changkaew, Kanjana; Yokoyama, Kazumasa; Kim, Hyun; Suthienkul, Orasa; Usui, Masaru; Tamura, Yutaka; Nakajima, Chie; Suzuki, Yasuhiko

    2016-10-01

    Amino acid substitutions providing quinolone resistance to Campyloabcter jejuni have been found in the quinolone resistance-determining region of protein DNA gyrase subunit A (GyrA), with the highest frequency at position 86 followed by position 90. In this study, wild-type and mutant recombinant DNA gyrase subunits were expressed in Escherichia coli and purified using Ni-NTA agarose column chromatography. Soluble 97 kDa GyrA and 87 kDa DNA gyrase subunit B were shown to reconstitute ATP-dependent DNA supercoiling activity. A quinolone-inhibited supercoiling assay demonstrated the roles of Thr86Ile, Thr86Ala, Thr86Lys, Asp90Asn, and Asp90Tyr amino acid substitutions in reducing sensitivity to quinolones. The marked effect of Thr86Ile on all examined quinolones suggested the advantage of this substitution in concordance with recurring isolation of quinolone-resistant C. jejuni. An analysis of the structure-activity relationship showed the importance of the substituent at position 8 in quinolones to overcome the effect of Thr86Ile. Sitafloxacin (SIT), which has a fluorinate cyclopropyl ring at R-1 and a chloride substituent at R-8, a characteristic not found in other quinolones, showed the highest inhibitory activity against all mutant C. jejuni gyrases including ciprofloxacin-resistant mutants. The results suggest SIT as a promising drug for the treatment of campylobacteriosis caused by CIP-resistant C. jejuni. Copyright © 2016 John Wiley & Sons, Ltd.

  9. Melatonin Anticancer Effects: Review

    Directory of Open Access Journals (Sweden)

    Luigi Di Bella

    2013-01-01

    Full Text Available Melatonin (N-acetyl-5-methoxytryptamine, MLT, the main hormone produced by the pineal gland, not only regulates circadian rhythm, but also has antioxidant, anti-ageing and immunomodulatory properties. MLT plays an important role in blood composition, medullary dynamics, platelet genesis, vessel endothelia, and in platelet aggregation, leukocyte formula regulation and hemoglobin synthesis. Its significant atoxic, apoptotic, oncostatic, angiogenetic, differentiating and antiproliferative properties against all solid and liquid tumors have also been documented. Thanks, in fact, to its considerable functional versatility, MLT can exert both direct and indirect anticancer effects in factorial synergy with other differentiating, antiproliferative, immunomodulating and trophic molecules that form part of the anticancer treatment formulated by Luigi Di Bella (Di Bella Method, DBM: somatostatin, retinoids, ascorbic acid, vitamin D3, prolactin inhibitors, chondroitin-sulfate. The interaction between MLT and the DBM molecules counters the multiple processes that characterize the neoplastic phenotype (induction, promotion, progression and/or dissemination, tumoral mutation. All these particular characteristics suggest the use of MLT in oncological diseases.

  10. Prevalence of quinolone resistance mechanisms and associations to minimum inhibitory concentrations in quinolone-resistant Escherichia coli isolated from humans and swine in Denmark

    DEFF Research Database (Denmark)

    Cavaco, Lina; Frimodt-Møller, Niels; Hasman, Henrik;

    2008-01-01

    Prevalence of quinolone resistance mechanisms and associations to minimum inhibitory concentrations (MICs) of nalidixic acid (NAL) and ciprofloxacin (CIP) were investigated in 124 Escherichia coli isolated from humans (n = 85) and swine (n = 39) in Denmark. The collection included 59 high-level CIP......-resistant isolates (MIC >= 4) from human (n = 51) and pig origin (n = 8) and 65 low-level CIP-resistant isolates (MIC >= 0.125) from human (n = 34) and pig origin (n = 31). Resistance by target modification was screened by PCR amplification and sequencing, of the quinolone resistance determining regions (QRDRs......A and qnrS genes conferring quinolone resistance by target protection were detected in two human low-level CIP-resistant isolates that did not display NAL resistance. As expected, target mutation in QRDRs was the most prevalent mechanism of quinolone resistance. This mechanism was complemented by efflux...

  11. Quinolone resistant campylobacter infections in Denmark: risk factors and clinical consequences

    DEFF Research Database (Denmark)

    Engberg, J.; Neimann, J.; Nielsen, E. M.;

    2004-01-01

    We integrated data on quinolone and macrolide susceptibility patterns with epidemiologic and typing data from Campylobacter jejuni and C. coli infections in two Danish counties. The mean duration of illness was longer for 86 patients with quinolone-resistant C. jejuni infections (median 13.2 days......) than for 381 patients with quinolone-sensitive C. jejuni infections (median 10.3 days, p = 0.001). Foreign travel, eating fresh poultry other than chicken and turkey, and swimming were associated with increased risk for quinolone-resistant C. jejuni infection. Eating fresh chicken (of presumably Danish...... origin) was associated with a decreased risk. Typing data showed an association between strains from retail food products and broiler chickens and quinolone-sensitive domestically acquired C. jejuni infections. An association between treatment with a fluoroquinolone before stool-specimen collection...

  12. [Investigation of plasmid-mediated quinolone resistance in Escherichia coli strains].

    Science.gov (United States)

    Aktepe, Orhan Cem; Aşık, Gülşah; Cetinkol, Yeliz; Biçmen, Meral; Gülay, Zeynep

    2012-01-01

    Quinolones are widely used antimicrobial agents, particularly for the treatment of infections caused by gram-negative bacilli such as E.coli. As a consequence, quinolone resistance has been increasing among this species in recent years. Bacterial resistance to quinolones usually results from mutations in the chromosomal genes which encode topoisomerases and also the expression of efflux pumps and loss of porines contributed to development of quinolone resistance. However, recent studies have shown that the spread and increase of quinolone resistance may be due to the transfer of plasmid-mediated genes. To date, three groups of plasmid-mediated quinolone resistance genes, namely qnr, aac(6')-Ib-cr, and qepA, have been described. The aim of this study was to investigate the presence of plasmid-mediated quinolone resistance genes in E.coli clinical isolates. A total of 112 quinolone-resistant E.coli strains isolated from different clinical specimens (84 urine, 16 blood, 10 wound, 2 bronchoalveolar lavage) of which 78 (69.6%) were extended-spectrum beta-lactamase (ESBL) positive, in Afyon Kocatepe University Hospital, Microbiology Laboratory were included in the study. In the isolates, qnrA, qnrB, qnrS, qnrC, qepA, and aac(6')-1b-cr plasmid genes were analysed by polymerase chain reaction (PCR). After aac(6')- 1b determinant was amplified by PCR, all aac(6')-1b positive amplicons were analyzed by digestion with BseGI restriction enzyme to identify aac(6')-1b-cr variant. It was found that, none of the strains horboured qnrA, qnrB, qnrS, qnrC and qepA genes, however, plasmid-mediated quinolone resistance gene aac(6')-1b-cr was found positive in 59.8% (67/112) of the strains. It was notable that 86.6% (58/67) of those isolates were ESBL producers. The rates of quinolone resistance among E.coli isolates infections were high in our region and an increasing trend has been observed in recent years. Our data indicated that the presence of plasmid- mediated resistance genes

  13. Comparative in vitro activities of nemonoxacin (TG-873870), a novel nonfluorinated quinolone, and other quinolones against clinical isolates.

    Science.gov (United States)

    Lauderdale, Tsai-Ling; Shiau, Yih-Ru; Lai, Jui-Fen; Chen, Hua-Chien; King, Chi-Hsin R

    2010-03-01

    The in vitro antibacterial activities of nemonoxacin (TG-873870), a novel nonfluorinated quinolone, against 770 clinical isolates were investigated. Nemonoxacin (tested as its malate salt, TG-875649) showed better in vitro activity than ciprofloxacin and levofloxacin against different species of staphylococci, streptococci, and enterococci, Neisseria gonorrhoeae, and Haemophilus influenzae. The in vitro activity of TG-875649 was also comparable to or better than that of moxifloxacin against these pathogens, which included ciprofloxacin-resistant, methicillin-resistant Staphylococcus aureus and levofloxacin-resistant Streptococcus pneumoniae.

  14. Serendipity in anticancer drug discovery.

    Science.gov (United States)

    Hargrave-Thomas, Emily; Yu, Bo; Reynisson, Jóhannes

    2012-01-10

    It was found that the discovery of 5.8% (84/1437) of all drugs on the market involved serendipity. Of these drugs, 31 (2.2%) were discovered following an incident in the laboratory and 53 (3.7%) were discovered in a clinical setting. In addition, 263 (18.3%) of the pharmaceuticals in clinical use today are chemical derivatives of the drugs discovered with the aid of serendipity. Therefore, in total, 24.1% (347/1437) of marketed drugs can be directly traced to serendipitous events confirming the importance of this elusive phenomenon. In the case of anticancer drugs, 35.2% (31/88) can be attributed to a serendipitous event, which is somewhat larger than for all drugs. The therapeutic field that has benefited the most from serendipity are central nervous system active drugs reflecting the difficulty in designing compounds to pass the blood-brain-barrier and the lack of laboratory-based assays for many of the diseases of the mind.

  15. Quantifying Pseudomonas aeruginosa quinolones and examining their interactions with lipids.

    Science.gov (United States)

    Palmer, Gregory C; Schertzer, Jeffrey W; Mashburn-Warren, Lauren; Whiteley, Marvin

    2011-01-01

    Pseudomonas aeruginosa produces a quorum sensing molecule termed the Pseudomonas Quinolone Signal (2-heptyl-3-hydroxy-4-quinolone; PQS) that regulates an array of genes involved in virulence. This chapter addresses four related techniques useful for detecting and quantifying PQS. First, extraction of PQS from complex mixtures (e.g. cell cultures) is described. Separation of PQS from extracts by Thin-Layer Chromatography (TLC) is used in combination with the natural fluorescence of the molecule for quantification. A second separation technique for the PQS precursor HHQ using High-Performance Liquid Chromatography (HPLC) is also described, and this assay exploits the molecule's characteristic absorbance for quantification. A third method for quantification of PQS from simple mixtures (e.g. enzyme assays) using fluorescence is outlined. Finally, a protocol for determining PQS interactions with membrane lipids through Fluorescence Resonance Energy Transfer (FRET) is presented. These techniques allow for quantification and characterization of PQS from diverse environments, a prerequisite to understanding the biological functions of QS molecules.

  16. Anticancer properties of polysaccharides isolated from fungi of the Basidiomycetes class.

    Science.gov (United States)

    Lemieszek, Marta; Rzeski, Wojciech

    2012-01-01

    Basidiomycete mushrooms represent a valuable source of biologically active compounds with anticancer properties. This feature is primarily attributed to polysaccharides and their derivatives. The anticancer potential of polysaccharides is linked to their origin, composition and chemical structure, solubility and method of isolation. Moreover, their activity can be significantly increased by chemical modifications. Anticancer effects of polysaccharides can be expressed indirectly (immunostimulation) or directly (cell proliferation inhibition and/or apoptosis induction). Among the wide range of polysaccharides with documented anticancer properties, lentinan, polysaccharide-K (PSK) and schizophyllan deserve special attention. These polysaccharides for many years have been successfully applied in cancer treatment and their mechanism of action is the best known.

  17. Responses of plasmid-mediated quinolone resistance genes and bacterial taxa to (fluoro)quinolones-containing manure in arable soil.

    Science.gov (United States)

    Xiong, Wenguang; Sun, Yongxue; Ding, Xueyao; Zhang, Yiming; Zhong, Xiaoxia; Liang, Wenfei; Zeng, Zhenling

    2015-01-01

    The aim of the present study was to investigate the fate of plasmid-mediated quinolone resistance (PMQR) genes and the disturbance of soil bacterial communities posed by (fluoro)quinolones (FQNs)-containing manure in arable soil. Representative FQNs (enrofloxacin (ENR), ciprofloxacin (CIP) and norfloxacin (NOR)), PMQR genes (qepA, oqxA, oqxB, aac(6')-Ib-cr and qnrS) and bacterial communities in untreated soil, +manure and +manure+FQNs groups were analyzed using culture independent methods. The significantly higher abundance of oqxA, oqxB and aac(6')-Ib-cr, and significantly higher abundance of qnrS in +manure group than those in untreated soil disappeared at day 30 and day 60, respectively. All PMQR genes (oqxA, oqxB, aac(6')-Ib-cr and qnrS) dissipated 1.5-1.7 times faster in +manure group than those in +manure+FQNs group. The disturbance of soil bacterial communities posed by FQNs-containing manure was also found. The results indicated that significant effects of PMQR genes (oqxA, oqxB, aac(6')-Ib and qnrS) on arable soils introduced by manure disappeared 2 month after manure application. FQNs introduced by manure slowed down the dissipation of PMQR genes. The presence of high FQNs provided a selective advantage for species affiliated to the phylum including Acidobacteria, Verrucomicrobia and Planctomycetes while suppressing Proteobacteria and Actinobacteria.

  18. A novel synthesis of carbon-labelled quinolone-3-carboxylic acid antibacterials

    Energy Technology Data Exchange (ETDEWEB)

    Carr, R.M.; Sutherland, D.R. (Glaxo Research and Development Ltd., Greenford (United Kingdom). Isotope Chemistry Group)

    1994-10-01

    3-Iodoquinolones were prepared from the corresponding quinolone-3-carboxylic acids by Hunsdiecker-type iododecarboxylation reactions with lead tetraacetate and iodine. Cyanation of the iodo compounds with mixtures of potassium [[sup 13]C]cyanide and copper (1) iodide, gave [3-[sup 13]C]cyanoquinolones which on acidic hydrolysis afforded quinolone-[3-[sup 13]C]carboxylic acids. In this way, nalidixic acid, an immediate precursor of norfloxacin, and quinolone WIN57273 were labelled with carbon-13 in the metabolically stable carboxylic acid fragment. (author).

  19. Synthesis and antibacterial evaluation of a new series of N-Alkyl-2-alkynyl/(E)-alkenyl-4-(1H)-quinolones.

    Science.gov (United States)

    Wube, Abraham; Guzman, Juan-David; Hüfner, Antje; Hochfellner, Christina; Blunder, Martina; Bauer, Rudolf; Gibbons, Simon; Bhakta, Sanjib; Bucar, Franz

    2012-07-09

    To gain further insight into the structural requirements of the aliphatic group at position 2 for their antimycobacterial activity, some N-alkyl-4-(1H)-quinolones bearing position 2 alkynyls with various chain length and triple bond positions were prepared and tested for in vitro antibacterial activity against rapidly-growing strains of mycobacteria, the vaccine strain Mycobacterium bovis BCG, and methicillin-resistant Staphylococcus aureus strains, EMRSA-15 and -16. The compounds were also evaluated for inhibition of ATP-dependent MurE ligase of Mycobacterium tuberculosis. The lowest MIC value of 0.5 mg/L (1.2-1.5 µM) was found against M. fortuitum and M. smegmatis. These compounds displayed no or only weak toxicity to the human lung fibroblast cell line MRC-5 at 100 µM concentration. The quinolone derivatives exhibited pronounced activity against the epidemic MRSA strains (EMRSA-15 and -16) with MIC values of 2-128 mg/L (5.3-364.7 µM), and M. bovis BCG with an MIC value of 25 mg/L (66.0-77.4 µM). In addition, the compounds inhibited the MurE ligase of M. tuberculosis with moderate to weak activity showing IC50 values of 200-774 µM. The increased selectivity towards mycobacterial bacilli with reference to MRC-5 cells observed for 2-alkynyl quinolones compared to their corresponding 2-alkenyl analogues serves to highlight the mycobacterial specific effect of the triple bond. Exploration of a terminal bromine atom at the side chain of N-alkyl-2-(E)-alkenyl-4-(1H)-quinolones showed improved antimycobacterial activity whereas a cyclopropyl residue at N-1 was suggested to be detrimental to antibacterial activity.

  20. Emergence of quinolone-resistant strains in Streptococcus pneumoniae isolated from paediatric patients since the approval of oral fluoroquinolones in Japan.

    Science.gov (United States)

    Takeuchi, Noriko; Ohkusu, Misako; Hoshino, Tadashi; Naito, Sachiko; Takaya, Akiko; Yamamoto, Tomoko; Ishiwada, Naruhiko

    2017-01-31

    Tosufloxacin (TFLX) is a fluoroquinolone antimicrobial agent. TFLX granules for children were initially released in Japan in 2010 to treat otitis media and pneumonia caused by drug-resistant bacteria, e.g. penicillin-resistant Streptococcus pneumoniae and beta-lactamase-negative, ampicillin-resistant Haemophilus influenzae. The evolution of bacterial resistance since TFLX approval is not known. To clarify the influence of quinolones administered to children since their approval, we examined the resistance mechanism of TFLX-resistant S. pneumoniae isolated from paediatric patients as well as patient clinical characteristics. TFLX-resistant strains (MIC ≥ 2 mg/L) were detected among clinical isolates of S. pneumoniae derived from children (≤15 years old) between 2010 and 2014. These strains were characterised based on quinolone resistance-determining regions (QRDRs), i.e. gyrA, gyrB, parC, and parE. In addition, the antimicrobial susceptibility, serotype, and multilocus sequence type of strains were determined, pulsed-field gel electrophoresis was performed, and patient clinical characteristics based on medical records were assessed for cases with underling TFLX-resistant strains. Among 1168 S. pneumoniae isolates, two TFLX-resistant strains were detected from respiratory specimens obtained from paediatric patients with frequent exposure to TFLX. Both strains had mutations in the QRDRs of gyrA and parC. One case exhibited gradual changes in the QRDR during the clinical course. This is the first study of quinolone-resistant S. pneumoniae isolated from children, including clinical data, in Japan. These data may help prevent increases in infections of quinolone-resistant S. pneumoniae in children; specifically, the results emphasise the importance of administering fluoroquinolones only in appropriate cases.

  1. Oral delivery of anticancer drugs

    DEFF Research Database (Denmark)

    Thanki, Kaushik; Gangwal, Rahul P; Sangamwar, Abhay T;

    2013-01-01

    The present report focuses on the various aspects of oral delivery of anticancer drugs. The significance of oral delivery in cancer therapeutics has been highlighted which principally includes improvement in quality of life of patients and reduced health care costs. Subsequently, the challenges...... incurred in the oral delivery of anticancer agents have been especially emphasized. Sincere efforts have been made to compile the various physicochemical properties of anticancer drugs from either literature or predicted in silico via GastroPlus™. The later section of the paper reviews various emerging...... trends to tackle the challenges associated with oral delivery of anticancer drugs. These invariably include efflux transporter based-, functional excipient- and nanocarrier based-approaches. The role of drug nanocrystals and various others such as polymer based- and lipid based...

  2. Acupuncture as anticancer treatment?

    Science.gov (United States)

    Kilian-Kita, Aneta; Püsküllüoglu, Mirosława; Krzemieniecki, Krzysztof

    2017-01-01

    The mystery of Traditional Chinese Medicine has been attracting people for years. Acupuncture, ranked among the most common services of Complementary and Alternative Medicine, has recently gained a lot of interest in the scientific world. Contemporary researchers have been continuously trying to shed light on its possible mechanism of action in human organism. Numerous studies pertaining to acupuncture’s application in cancer symptoms or treatment-related side effects management have already been published. Moreover, since the modern idea of acupuncture’s immunomodulating effect seems to be promising, scientists have propounded a concept of its potential application as part of direct anti-tumor therapy. In our previous study we summarized possible use of acupuncture in management of cancer symptoms and treatment-related ailments, such as chemotherapy-induced nausea and vomiting, pain, xerostomia, vasomotor symptoms, neutropenia, fatigue, anxiety, insomnia, lymphoedema after mastectomy and peripheral neuropathy. This article reviews the studies concerning acupuncture as a possible tool in modern anticancer treatment. PMID:28239282

  3. Coumarin: a promising scaffold for anticancer agents.

    Science.gov (United States)

    Kaur, Manjinder; Kohli, Swarandeep; Sandhu, Sonali; Bansal, Yogita; Bansal, Gulshan

    2015-01-01

    Coumarin enjoys an important place in drug discovery process due to its presence in diversity of biologically active compounds. Many compounds of plant origin are derivatives of coumarin. Taking these natural products as lead, research groups across the globe have designed and synthesized numerous coumarin analogues for treatment of varied diseases. Cancer is one of the dreadful chronic diseases, and many drugs are available for its treatment. However, due to heterogeneity of cancer, the search is still on to develop drugs for specific types of cancers. The present review is an attempt to study various coumarin derivatives of natural as well as synthetic origins, which are identified or developed for the treatment of different types of cancers. Herein, we have classified various anticancer coumarin derivatives on the basis of their origin as well as substitution around it. These are discussed under the headings of natural, semi-synthetic and synthetic coumarin derivatives. The synthetic coumarin derivatives are further classified as mono-, di- and poly-substituted and fused coumarin derivatives. Of the six positions available for substituents on coumarin nucleus, only three positions (C-3, C-4 and C-7) are exploited for the selection of functional groups appropriate for anticancer activity. The other positions (C-5, C-6 and C-8) are either unexplored or very less exploited. The present review is expected to provide the medicinal chemists a guide to choose new functional groups for substitution at different positions of coumarin nucleus for development of novel compounds for the treatment of a specific type of cancer.

  4. Overcoming target-mediated quinolone resistance in topoisomerase IV by introducing metal-ion-independent drug-enzyme interactions.

    Science.gov (United States)

    Aldred, Katie J; Schwanz, Heidi A; Li, Gangqin; McPherson, Sylvia A; Turnbough, Charles L; Kerns, Robert J; Osheroff, Neil

    2013-12-20

    Quinolones, which target gyrase and topoisomerase IV, are the most widely prescribed antibacterials worldwide. Unfortunately, their use is threatened by the increasing prevalence of target-mediated drug resistance. Greater than 90% of mutations that confer quinolone resistance act by disrupting enzyme-drug interactions coordinated by a critical water-metal ion bridge. Quinazolinediones are quinolone-like drugs but lack the skeletal features necessary to support the bridge interaction. These compounds are of clinical interest, however, because they retain activity against the most common quinolone resistance mutations. We utilized a chemical biology approach to determine how quinazolinediones overcome quinolone resistance in Bacillus anthracis topoisomerase IV. Quinazolinediones that retain activity against quinolone-resistant topoisomerase IV do so primarily by establishing novel interactions through the C7 substituent, rather than the drug skeleton. Because some quinolones are highly active against human topoisomerase IIα, we also determined how clinically relevant quinolones discriminate between the bacterial and human enzymes. Clinically relevant quinolones display poor activity against topoisomerase IIα because the human enzyme cannot support drug interactions mediated by the water-metal ion bridge. However, the inclusion of substituents that allow quinazolinediones to overcome topoisomerase IV-mediated quinolone resistance can cause cross-reactivity against topoisomerase IIα. Therefore, a major challenge in designing drugs that overcome quinolone resistance lies in the ability to identify substituents that mediate strong interactions with the bacterial, but not the human, enzymes. On the basis of our understanding of quinolone-enzyme interactions, we have identified three compounds that display high activity against quinolone-resistant B. anthracis topoisomerase IV but low activity against human topoisomerase IIα.

  5. New luminophor-activators based on (fluoro)quinolone antibacterials

    Energy Technology Data Exchange (ETDEWEB)

    Polishchuk, A.V. [Joint Biotechnology Laboratory, Department of Chemistry, University of Turku, BioCity 6A, FIN-20520 Turku (Finland); Institute of Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, pr.100-let Vladivostoku, 159, Vladivostok 690022 (Russian Federation); Karaseva, E.T. [Institute of Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, pr.100-let Vladivostoku, 159, Vladivostok 690022 (Russian Federation); Korpela, T. [Joint Biotechnology Laboratory, Department of Chemistry, University of Turku, BioCity 6A, FIN-20520 Turku (Finland); Karasev, V.E. [Institute of Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, pr.100-let Vladivostoku, 159, Vladivostok 690022 (Russian Federation)], E-mail: karasev@ich.dvo.ru

    2008-11-15

    It was shown that (fluoro)quinolone antibiotics form strongly fluorescent solid-state complexes with Eu(III) and Tb(III) lanthanide ions, with a wavelength red-shift beneficial for applications to greenhouse-cover polymers. Complexes with optimal properties were prepared by the mechanical activation of fine-dispersed composite mixtures with the lanthanide salts. The spectral properties, photo-stability to UV-light, and compatibility with the polyethylene matrix were investigated. The formulation additives of the tablet forms of the antibiotic medicines did not quench the fluorescence from the lanthanide ions. Therefore, the outdated drug forms of the antibiotics can serve as cheap recyclable sources for the covering material of greenhouses. In addition, diphenylguanidine (DPG) was investigated as a coligand. DPG enhanced fluorescence of the fluoroquinolone complexes by decreasing the non-radiative energy loss through O-H vibration of H{sub 2}O.

  6. Quinolones for the Treatment of Neisseria Gonorrhoeae and Chlamydia Trachomatis

    Directory of Open Access Journals (Sweden)

    Sebastian Faro

    1993-01-01

    Full Text Available The most commonly sexually transmitted bacteria are Neisseria gonorrhoeae and Chlamydia trachomatis. The quinolones ofloxacin and ciprofloxacin have been shown to have activity against both of these bacteria in vitro and in vivo. Ofloxacin is particularly well suited for the treatment of N. gonorrhoeae and C. trachomatis cervical infection, which can be considered the earliest manifestation of pelvic inflammatory disease (PID. Not only can ofloxacin be effectively used as a single agent, it is also useful in treating urinary tract infections caused by Enterobacteriaceae. Although it has moderate activity against anaerobes in general, ofloxacin does have activity against the anaerobes commonly isolated from female patients with soft tissue pelvic infections. Thus, ofloxacin has the potential for being utilized to treat early salpingitis.

  7. The DNA gyrase-quinolone complex. ATP hydrolysis and the mechanism of DNA cleavage

    DEFF Research Database (Denmark)

    Kampranis, S C; Maxwell, A

    1998-01-01

    Quinolone binding to the gyrase-DNA complex induces a conformational change that results in the blocking of supercoiling. Under these conditions gyrase is still capable of ATP hydrolysis which now proceeds through an alternative pathway involving two different conformations of the enzyme (Kampranis......, S. C., and Maxwell, A. (1998) J. Biol. Chem. 269, 22606-22614). The kinetics of ATP hydrolysis via this pathway have been studied and found to differ from those of the reaction of the drug-free enzyme. The quinolone-characteristic ATPase rate is DNA-dependent and can be induced in the presence...... of DNA fragments as small as 20 base pairs. By observing the conversion of the ATPase rate to the quinolone characteristic rate, the formation and dissociation of the gyrase-DNA-quinolone complex can be monitored. Comparison of the time dependence of the conversion of the gyrase ATPase with that of DNA...

  8. Chemical structure and pharmacokinetics of novel quinolone agents represented by avarofloxacin, delafloxacin, finafloxacin, zabofloxacin and nemonoxacin.

    Science.gov (United States)

    Kocsis, Bela; Domokos, J; Szabo, D

    2016-05-23

    Quinolones are potent antimicrobial agents with a basic chemical structure of bicyclic ring. Fluorine atom at position C-6 and various substitutions on the basic quinolone structure yielded fluoroquinolones, namely norfloxacin, ciprofloxacin, levofloxacin, moxifloxacin and numerous other agents. The target molecules of quinolones and fluoroquinolones are bacterial gyrase and topoisomerase IV enzymes. Broad-spectrum and excellent tissue penetration make fluoroquinolones potent agents but their toxic side effects and increasing number of resistant pathogens set limits on their use. This review focuses on recent advances concerning quinolones and fluoroquinolones, we will be summarising chemical structure, mode of action, pharmacokinetic properties and toxicity. We will be describing fluoroquinolones introduced in clinical trials, namely avarofloxacin, delafloxacin, finafloxacin, zabofloxacin and non-fluorinated nemonoxacin. These agents have been proved to have enhanced antibacterial effect even against ciprofloxacin resistant pathogens, and found to be well tolerated in both oral and parenteral administrations. These features are going to make them potential antimicrobial agents in the future.

  9. Evaluating the impact of a novel restricted reimbursement policy for quinolone antibiotics: A time series analysis

    Directory of Open Access Journals (Sweden)

    Manns Braden

    2012-08-01

    Full Text Available Abstract Background Publicly-funded drug plans often use prior authorization policies to limit drug prescribing. To guide physician prescribing of a class of antibiotics with broad antimicrobial activity (quinolone antibiotics in accordance with new prescribing guidelines, Alberta’s provincial health ministry implemented a new mechanism for formulary restriction entitled the optional special authorization (OSA program. We conducted an observational study to determine the impact of this new formulary restriction policy on antimicrobial prescription rates as well as any clinical consequences. Methods Quinolone antibiotic use, and adherence with quinolone prescribing guidelines, was assessed before and after implementation of the OSA program in patients with common outpatient infections using an administrative data cohort and a chart review cohort, respectively. At the same time this policy was implemented to limit quinolone prescribing, two new quinolone antibiotics were added to the formulary. Using administrative data, we analysed a total of 397,534 unique index visits with regard to overall antibiotic utilization, and through chart review, we analysed 1681 charts of patients with infections of interest to determine the indications for quinolone usage. Results Using segmented regression models adjusting for age, sex and physician enrollment in the OSA program, there was no statistically significant change in the monthly rate of all quinolone use (−3.5 (95% CI −5.5, 1.4 prescriptions per 1000 index visits following implementation of the OSA program (p = 0.74. There was a significant level change in the rate of quinolone antibiotic use for urinary tract infection (−33.6 (95% CI: -23.8, -43.4 prescriptions and upper respiratory tract infection (−16.1 (95%CI: -11.6, -20.6 prescriptions per 1000 index visits. Among quinolone prescriptions identified on chart review, 42.5% and 58.5% were consistent with formulary guidelines before and

  10. Dynamics of Quinolone Resistance in Fecal Escherichia coli of Finishing Pigs after Ciprofloxacin Administration

    OpenAIRE

    Huang, Kang; Xu, Chang-Wen; Zeng, Bo; XIA, Qing-Qing; Zhang, An-Yun; LEI, Chang-Wei; Guan, Zhong-Bin; Cheng, Han; Wang, Hong-ning

    2014-01-01

    ABSTRACT Escherichia coli resistance to quinolones has now become a serious issue in large-scale pig farms of China. It is necessary to study the dynamics of quinolone resistance in fecal Escherichia coli of pigs after antimicrobial administration. Here, we present the hypothesis that the emergence of resistance in pigs requires drug accumulation for 7 days or more. To test this hypothesis, 26 pigs (90 days old, about 30 kg) not fed any antimicrobial after weaning were selected and divided in...

  11. Triterpenoids of Marine Origin as Anti-Cancer Agents

    Directory of Open Access Journals (Sweden)

    Yong-Xin Li

    2013-07-01

    Full Text Available Triterpenoids are the most abundant secondary metabolites present in marine organisms, such as marine sponges, sea cucumbers, marine algae and marine-derived fungi. A large number of triterpenoids are known to exhibit cytotoxicity against a variety of tumor cells, as well as anticancer efficacy in preclinical animal models. In this review efforts have been taken to review the structural features and the potential use of triterpenoids of marine origin to be used in the pharmaceutical industry as potential anti-cancer drug leads.

  12. [Multiresidue determination of quinolones in animal and fishery products by HPLC].

    Science.gov (United States)

    Chonan, Takao; Fujimoto, Toru; Inoue, Maki; Tazawa, Teijiro; Ogawa, Hiroshi

    2008-06-01

    A simple and rapid multiresidue method was developed for the determination of twelve quinolones (ciprofloxacin, danofloxacin, difloxacin, enrofloxacin, flumequine, marbofloxacin, nalidixic acid, norfloxacin, ofloxacin, orbifloxacin, oxolinic acid and sarafloxacin) in muscle, liver, chicken eggs, milk, prawn and rainbow trout. The quinolones were extracted from a sample with acetonitrile-water (95 : 5). A fifth part of the filtered extract was diluted with water to keep the acetonitrile ratio at ca. 60%, and passed through a C18 mini-column. The eluate was evaporated to dryness, and the residues were dissolved in methanol-water (30 : 70) for HPLC analysis. The quinolones were separated on a Inertsil ODS-3V column (4.6 mm i.d.x250 mm) with a gradient system of 0.1% phosphoric acid-acetonitrile as the mobile phase, with fluorescence detection.No interfering peak was found on the chromatograms of animal and fishery products, except for milk. The recoveries of the quinolones were over 60% from the animal and fishery products fortified at 0.1 microg/g, and the quantification limits of the quinolones were 0.005 microg/g. This proposed method was found to be effective and suitable for the screening of the quinolones in animal and fishery products.

  13. Genotoxicity of quinolone antibiotics in chlorination disinfection treatment: formation and QSAR simulation.

    Science.gov (United States)

    Li, Min; Wei, Dongbin; Du, Yuguo

    2016-10-01

    Lots of unexpected disinfection by-products were formed during the chlorination disinfection of contaminated water bodies, leading to a potential threat to human health and ecological safety. In this study, SOS/umu assay was used to trace the genotoxicity variation of 20 quinolone compounds during the chlorination disinfection. Furthermore, two- and three-dimensional quantitative structure-activity relationship models were developed based on the electronic and hydrophobic properties of the quinolones, which were used to quantify the impact of the different structural features of the compounds on their genotoxicity variation. The results revealed that quinolones bearing hydrophilic substituents with less H-bond donors and negative charge at the 1-position of the quinolone ring exhibited a positive correlation with genotoxicity elevation. More notably, the chlorination of quinolones in both ultrapure water and secondary effluent matrices provided comparable levels of genotoxicity, indicating that our research could potentially be used to evaluate the environmental risk of quinolone antibiotics in chlorination disinfection treatment.

  14. Structural insights into the quinolone resistance mechanism of Mycobacterium tuberculosis DNA gyrase.

    Directory of Open Access Journals (Sweden)

    Jérémie Piton

    Full Text Available Mycobacterium tuberculosis DNA gyrase, an indispensable nanomachine involved in the regulation of DNA topology, is the only type II topoisomerase present in this organism and is hence the sole target for quinolone action, a crucial drug active against multidrug-resistant tuberculosis. To understand at an atomic level the quinolone resistance mechanism, which emerges in extensively drug resistant tuberculosis, we performed combined functional, biophysical and structural studies of the two individual domains constituting the catalytic DNA gyrase reaction core, namely the Toprim and the breakage-reunion domains. This allowed us to produce a model of the catalytic reaction core in complex with DNA and a quinolone molecule, identifying original mechanistic properties of quinolone binding and clarifying the relationships between amino acid mutations and resistance phenotype of M. tuberculosis DNA gyrase. These results are compatible with our previous studies on quinolone resistance. Interestingly, the structure of the entire breakage-reunion domain revealed a new interaction, in which the Quinolone-Binding Pocket (QBP is blocked by the N-terminal helix of a symmetry-related molecule. This interaction provides useful starting points for designing peptide based inhibitors that target DNA gyrase to prevent its binding to DNA.

  15. Interplay between intrinsic and acquired resistance to quinolones in Stenotrophomonas maltophilia.

    Science.gov (United States)

    García-León, Guillermo; Salgado, Fabiola; Oliveros, Juan Carlos; Sánchez, María Blanca; Martínez, José Luis

    2014-05-01

    To analyse whether the mutation-driven resistance-acquisition potential of a given bacterium might be a function of its intrinsic resistome, quinolones were used as selective agents and Stenotrophomonas maltophilia was chosen as a bacterial model. S. maltophilia has two elements - SmQnr and SmeDEF - that are important in intrinsic resistance to quinolones. Using a battery of mutants in which either or both of these elements had been removed, the apparent mutation frequency for quinolone resistance and the phenotype of the selected mutants were found to be related to the intrinsic resistome and also depended on the concentration of the selector. Most mutants had phenotypes compatible with the overexpression of multidrug efflux pump(s); SmeDEF overexpression was the most common cause of quinolone resistance. Whole genome sequencing showed that mutations of the SmeRv regulator, which result in the overexpression of the efflux pump SmeVWX, are the cause of quinolone resistance in mutants not overexpressing SmeDEF. These results indicate that the development of mutation-driven antibiotic resistance is highly dependent on the intrinsic resistome, which, at least for synthetic antibiotics such as quinolones, did not develop as a response to the presence of antibiotics in the natural ecosystems in which S. maltophilia evolved.

  16. Screening of quinolone antibiotic residues in chicken meat and beef sold in the markets of Ankara, Turkey.

    Science.gov (United States)

    Er, Buket; Onurdag, Fatma Kaynak; Demirhan, Burak; Ozgacar, Selda Özgen; Oktem, Aysel Bayhan; Abbasoglu, Ufuk

    2013-08-01

    This study aimed to find the effects of quinolone antibiotics in chicken and beef used in Ankara, Turkey. Total number of 127 chicken and 104 beef meat samples were collected randomly from local markets for analysis. Extraction and determination of quinolones were made by ELISA procedure. One hundred eighteen of 231 (51.1%) examined chicken meat and beef samples were found to contain quinolone antibiotic residue. Among the chicken meat and beef samples, 58 (45.7%) of chicken meat samples and 60 (57.7%) of beef meat samples were positive for quinolones, respectively. The mean levels (±SE) of quinolones were found to be 30.81 ± 0.45 µg/kg and 6.64 ± 1.11 µg/kg in chicken and beef samples, respectively. This study indicated that some chicken and beef meat sold in Ankara contains residues of quinolone antibiotics.

  17. Antimalarial therapy selection for quinolone resistance among Escherichia coli in the absence of quinolone exposure, in tropical South America.

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    Ross J Davidson

    Full Text Available BACKGROUND: Bacterial resistance to antibiotics is thought to develop only in the presence of antibiotic pressure. Here we show evidence to suggest that fluoroquinolone resistance in Escherichia coli has developed in the absence of fluoroquinolone use. METHODS: Over 4 years, outreach clinic attendees in one moderately remote and five very remote villages in rural Guyana were surveyed for the presence of rectal carriage of ciprofloxacin-resistant gram-negative bacilli (GNB. Drinking water was tested for the presence of resistant GNB by culture, and the presence of antibacterial agents and chloroquine by HPLC. The development of ciprofloxacin resistance in E. coli was examined after serial exposure to chloroquine. Patient and laboratory isolates of E. coli resistant to ciprofloxacin were assessed by PCR-sequencing for quinolone-resistance-determining-region (QRDR mutations. RESULTS: In the very remote villages, 4.8% of patients carried ciprofloxacin-resistant E. coli with QRDR mutations despite no local availability of quinolones. However, there had been extensive local use of chloroquine, with higher prevalence of resistance seen in the villages shortly after a Plasmodium vivax epidemic (p<0.01. Antibacterial agents were not found in the drinking water, but chloroquine was demonstrated to be present. Chloroquine was found to inhibit the growth of E. coli in vitro. Replica plating demonstrated that 2-step QRDR mutations could be induced in E. coli in response to chloroquine. CONCLUSIONS: In these remote communities, the heavy use of chloroquine to treat malaria likely selected for ciprofloxacin resistance in E. coli. This may be an important public health problem in malarious areas.

  18. Occurrence of (fluoro)quinolones and (fluoro)quinolone resistance in soil receiving swine manure for 11 years.

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    Xu, Yonggang; Yu, Wantai; Ma, Qiang; Zhou, Hua

    2015-10-15

    Because of the widespread use of antibiotics in animal breeding, the agricultural application of animal manure can lead to the introduction of antibiotics, antibiotic-resistant bacteria and antibiotic resistance genes to the soil and surrounding environment, which may pose a threat to public health. In this study, we investigated the status of (fluoro)quinolone (FQ) residues and FQ resistance levels in soil with and without receiving long-term swine manure. Six FQs (pipemidic acid, lomefloxacin, enrofloxacin, norfloxacin, ciprofloxacin, and ofloxacin) were only detected in manured soil, with individual concentrations ranging from below the detection limit to 27.2 μg kg(-1) and increasing with the increase in swine manure application rates. Higher load rates of swine manure yielded a higher number of ciprofloxacin-resistant (CIPr) bacteria after spreading. A total of 24 CIPr bacterial isolates were obtained from the tested soil, which belonged to four phyla (Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes) or were related to nine different genera. Only 18 isolates from manured soil were positive for five plasmid-mediated quinolone resistance (PMQR) genes (aac(6')-Ib-cr, qnrD, qepA, oqxA, and oqxB). To our knowledge, this study is the first to examine the occurrence of PMQR genes in FQ-resistant bacteria from the soil environment. A similar result was observed for the total DNA from soil, with the exception of aac(6')-Ib being detected in the control sample. The absolute and relative abundances of total PMQR genes also increased with fertilization quantity. Significant correlations were observed between FQ resistance levels and FQ concentrations. These results indicated that the agricultural application of swine manure led to FQ residues and enhanced FQ resistance. This investigation provides baseline data on FQ resistance profiles in soils receiving long-term swine manure.

  19. Preclinical Evidence on the Anticancer Properties of Food Peptides.

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    Rajendran, Subin R C K; Ejike, Chukwunonso E C C; Gong, Min; Hannah, William; Udenigwe, Chibuike C

    2017-01-01

    Natural, synthetic and analogues of peptides have shown prospects for application in cancer chemotherapy. Notably, some food protein-derived peptides are known to possess anticancer activities in cultured cancer cells, and also in animal cancer models via different mechanisms including induction of apoptosis, cell cycle arrest, cellular membrane disruption, inhibition of intracellular signalling, topoisomerases and proteases, and antiangiogenic activity. Although the mechanism of several anticancer food peptides is yet to be clearly elucidated, there is potential for practical applications of the peptides as functional food and nutraceutical ingredients, especially in adjuvant cancer therapy. This review describes the aetiological mechanisms of cancers and the production, structures, mechanisms of action, availability, and cellular and physiological anticancer activities of the food peptides.

  20. MEDICINAL PLANTS WITH POTENTIAL ANTICANCER ACTIVITIES: A REVIEW

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    Narah Merina

    2012-06-01

    Full Text Available Plants have been the beacon of therapeutic sources for curing diseases from times immemorial. Medicinal plants with their isolated lead molecules are also used as an alternative medicine for treating neoplastic cells. Neoplastic cells are the anomalous proliferation of cells in the body which cause cancer. Diverse efficient compounds derived from natural products have been isolated as anticancer agents. These chemical compounds are formulated with a view to create effective drugs against cancer. Some of the lead molecules isolated from different medicinal plants are already in use to treat cancer and chemotherapeutic side effects. These potential and successful anticancer molecules include Vincristine, Vinblastin, Taxol, Camptothecin and Podophyllotoxin. This paper deals with the selective medicinal plants having anticancer properties which could be further designed to produce cancer curing drugs.

  1. Alkaloids Isolated from Natural Herbs as the Anticancer Agents

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    Jin-Jian Lu

    2012-01-01

    Full Text Available Alkaloids are important chemical compounds that serve as a rich reservoir for drug discovery. Several alkaloids isolated from natural herbs exhibit antiproliferation and antimetastasis effects on various types of cancers both in vitro and in vivo. Alkaloids, such as camptothecin and vinblastine, have already been successfully developed into anticancer drugs. This paper focuses on the naturally derived alkaloids with prospective anticancer properties, such as berberine, evodiamine, matrine, piperine, sanguinarine, and tetrandrine, and summarizes the mechanisms of action of these compounds. Based on the information in the literature that is summarized in this paper, the use of alkaloids as anticancer agents is very promising, but more research and clinical trials are necessary before final recommendations on specific alkaloids can be made.

  2. Anti-cancer natural products isolated from chinese medicinal herbs

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    Wu Guosheng

    2011-07-01

    Full Text Available Abstract In recent years, a number of natural products isolated from Chinese herbs have been found to inhibit proliferation, induce apoptosis, suppress angiogenesis, retard metastasis and enhance chemotherapy, exhibiting anti-cancer potential both in vitro and in vivo. This article summarizes recent advances in in vitro and in vivo research on the anti-cancer effects and related mechanisms of some promising natural products. These natural products are also reviewed for their therapeutic potentials, including flavonoids (gambogic acid, curcumin, wogonin and silibinin, alkaloids (berberine, terpenes (artemisinin, β-elemene, oridonin, triptolide, and ursolic acid, quinones (shikonin and emodin and saponins (ginsenoside Rg3, which are isolated from Chinese medicinal herbs. In particular, the discovery of the new use of artemisinin derivatives as excellent anti-cancer drugs is also reviewed.

  3. Rapid determination of quinolones in cosmetic products by ultra high performance liquid chromatography with tandem mass spectrometry.

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    Liu, Shao-Ying; Huang, Xi-Hui; Wang, Xiao-Fang; Jin, Quan; Zhu, Guo-Nian

    2014-05-01

    This study developed an improved analytical method for the simultaneous quantification of 13 quinolones in cosmetics by ultra high performance liquid chromatography combined with ESI triple quadrupole MS/MS under the multiple reaction monitoring mode. The analytes were extracted and purified by using an SPE cartridge. The limits of quantification ranged from 0.03 to 3.02 μg/kg. The precision for determining the quinolones was quinolones in real cosmetic samples.

  4. Quinolone resistance in absence of selective pressure: the experience of a very remote community in the Amazon forest.

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    Lucia Pallecchi

    Full Text Available BACKGROUND: Quinolones are potent broad-spectrum bactericidal agents increasingly employed also in resource-limited countries. Resistance to quinolones is an increasing problem, known to be strongly associated with quinolone exposure. We report on the emergence of quinolone resistance in a very remote community in the Amazon forest, where quinolones have never been used and quinolone resistance was absent in 2002. METHODS: The community exhibited a considerable level of geographical isolation, limited contact with the exterior and minimal antibiotic use (not including quinolones. In December 2009, fecal carriage of antibiotic resistant Escherichia coli was investigated in 120 of the 140 inhabitants, and in 48 animals reared in the community. All fluoroquinolone-resistant isolates were genotyped and characterized for the mechanisms of plasmid- and chromosomal-mediated quinolone resistance. PRINCIPAL FINDINGS: Despite the characteristics of the community remained substantially unchanged during the period 2002-2009, carriage of quinolone-resistant E. coli was found to be common in 2009 both in humans (45% nalidixic acid, 14% ciprofloxacin and animals (54% nalidixic acid, 23% ciprofloxacin. Ciprofloxacin-resistant isolates of human and animal origin showed multidrug resistance phenotypes, a high level of genetic heterogeneity, and a combination of GyrA (Ser83Leu and Asp87Asn and ParC (Ser80Ile substitutions commonly observed in fluoroquinolone-resistant clinical isolates of E. coli. CONCLUSIONS: Remoteness and absence of antibiotic selective pressure did not protect the community from the remarkable emergence of quinolone resistance in E. coli. Introduction of the resistant strains from antibiotic-exposed settings is the most likely source, while persistence and dissemination in the absence of quinolone exposure is likely mostly related with poor sanitation. Interventions aimed at reducing the spreading of resistant isolates (by improving sanitation

  5. Study of fluorescence characteristics of the charge-transfer reaction of quinolone agents with bromanil

    Science.gov (United States)

    Li, Wen-Ying; Chen, Xiao-Fang; Xuan, Chun-Sheng

    2009-01-01

    A spectrofluorimetric method was discussed for the determination of three antibacterial quinolone derivatives, ofloxacin (OFL), norfloxacin (NOR) and ciprofloxacin (CIP) through charge-transfer complexation (CTC) with 2,3,5,6-tetrabromo-1,4-benzoquinone (bromanil, TBBQ). The method was based on the reaction of these drugs as n-electron donors with the π-acceptor TBBQ. TBBQ was found to react with these drugs to produce a kind of yellow complexes and the fluorescence intensities of the complexes were enhanced by 29-36 times more than those of the corresponding monomers. UV-vis, 1H NMR and XPS techniques were used to study the complexes formed. The various experimental parameters affecting the fluorescence intensity were studied and optimized. Under optimal reaction conditions, the rectilinear calibration graphs were obtained in the concentration range of 0.021-2.42 μg mL -1, 0.017-2.63 μg mL -1 and 0.019-2.14 μg mL -1 for OFL, NOR and CIP, respectively. The methods developed were applied successfully to the determination of the subject drugs in their pharmaceutical dosage forms with good precision and accuracy compared to official and reported methods as revealed by t- and F-tests.

  6. Artemisinin–Second Career as Anticancer Drug?

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    Thomas Efferth

    2015-10-01

    Full Text Available Artemisinin represents a showcase example not only for the activity of medicinal herbs deriving from traditional chinese medicine, but for phytotherapy in general. Its isolation from Sweet Wormwood (qinhao, Artemisia annua L. represents the starting point for an unprecedent success story in the treatment of malaria worldwide. Beyond the therapeutic value against Plasmodium parasites, it turned out in recent years that the bioactivity of artemisinin is not restricted to malaria. We and others found that this sesquiterpenoid also exerts profound anticancer activity in vitro and in vivo. Artemisinin-type drugs exert multi-factorial cellular and molecular actions in cancer cells. Ferrous iron reacts with artemisinin, which leads to the formation of reactive oxygen species and ultimately to a plethora anticancer effects of artemisinins, e.g. expression of antioxidant response genes, cell cycle arrest (G1 as well as G2 phase arrests, DNA damage that is repaird by base excision repair, homogous recombination and non-homologous end-joining, as well as different modes of cell death (intrinsic and extrinsic apoptosis, autophagy, necrosis, necroptosis, oncosis, and ferroptosis. Furthermore, artemisinins inhibit neoangiogenesis in tumors. The signaling of major transcription factors (NF-κB, MYC/MAX, AP-1, CREBP, mTOR etc. and signaling pathways are affected by artemisinins (e.g. Wnt/β-catenin pathway, AMPK pathway, metastatic pathways, nitric oxide signaling, and others. Several case reports on the compassionate use of artemisinins as well as clinical Phase I/II pilot studies indicate the clinical activity of artemisinins in veterinary and human cancer patients. Larger scale of Phase II and III clinical studies are required now to further develop artemisinin-type compounds as novel anticancer drugs.

  7. Rh(III) and Ru(II)-catalyzed site-selective C-H alkynylation of quinolones.

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    Kang, Dahye; Hong, Sungwoo

    2015-04-17

    C2- and C5-alkynylated quinolone scaffolds are core structures of numerous biologically active molecules. Utilizing TIPS-EBX as an alkynylating agent, we have developed an efficient and site-selective C5 alkynylation of 4-quinolones that is directed by the weakly coordinating carbonyl group. In addition, Ru(II) catalyzed C2-selective alkynylation was successfully realized via N-pyrimidyl group-directed cross-couplings to access valuable C2-alkynylated 4-quinolones. This strategy provides direct access to the C2 or C5 alkynylated 4-quinolones. Furthermore, the reaction was applied to isoquinolones for C3-selective alkynylation.

  8. Synthesis of Novel Pyrido[4,3-e][1,2,4]triazino[3,2-c][1,2,4]thiadiazine 6,6-dioxide Derivatives with Potential Anticancer Activity

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    Jarosław Sławiński

    2015-12-01

    Full Text Available A series of novel 3-/2,3-substituted pyrido[4,3-e][1,2,4]triazino[3,2-c][1,2,4]thiadiazine 6,6-dioxides 4–28 have been synthesized by the reaction of 3-amino-2-(4-thioxo-1,4-dihydropyridin-3-yl-sulfonylguanidine with either 2-oxoalkanoic acids and its esters, or phenylglyoxylic hydrates in glacial acetic acid. Some of them exhibited reasonable or moderate anticancer activity toward human cancer cell lines, HCT-116, MCF-7 and HeLa. The structure of this novel heterocyclic ring system was confirmed by 1D-NMR and 2D-NMR spectroscopic data including COSY, ROESY and HMBC, elemental analyses and MS spectrometry.

  9. [The history of the development and changes of quinolone antibacterial agents].

    Science.gov (United States)

    Takahashi, Hisashi; Hayakawa, Isao; Akimoto, Takeshi

    2003-01-01

    The quinolones, especially the new quinolones (the 6-fluoroquinolones), are the synthetic antibacterial agents to rival the Beta-lactam and the macrolide antibacterials for impact in clinical usage in the antibacterial therapeutic field. They have a broad antibacterial spectrum of activity against Gram-positive, Gram-negative and mycobacterial pathogens as well as anaerobes. Further, they show good-to-moderate oral absorption and tissue penetration with favorable pharmacokinetics in humans resulting in high clinical efficacy in the treatment of many kinds of infections. They also exhibit excellent safety profiles as well as those of oral Beta-lactam antibiotics. The bacterial effects of quinolones inhibit the function of bacterial DNA gyrase and topoisomerase IV. The history of the development of the quinolones originated from nalidixic acid (NA), developed in 1962. In addition, the breakthrough in the drug design for the scaffold and the basic side chains have allowed improvements to be made to the first new quinolone, norfloxacin (NFLX), patented in 1978. Although currently more than 10,000 compounds have been already synthesized in the world, only two percent of them were developed and tested in clinical studies. Furthermore, out of all these compounds, only twenty have been successfully launched into the market. In this paper, the history of the development and changes of the quinolones are described from the first quinolone, NA, via, the first new quinolone (6-fluorinated quinolone) NFLX, to the latest extended-spectrum quinolone antibacterial agents against multi-drug resistant bacterial infections. NA has only modest activity against Gram-negative bacteria and low oral absorption, therefore a suitable candidate for treatment of systemic infections (UTIs) is required. Since the original discovery of NA, a series of quinolones, which are referred to as the old quinolones, have been developed leading to the first new quinolone, NFLX, with moderate improvements

  10. Efficacy of a non-hypercalcemic vitamin-D2 derived anti-cancer agent (MT19c and inhibition of fatty acid synthesis in an ovarian cancer xenograft model.

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    Richard G Moore

    Full Text Available BACKGROUND: Numerous vitamin-D analogs exhibited poor response rates, high systemic toxicities and hypercalcemia in human trials to treat cancer. We identified the first non-hypercalcemic anti-cancer vitamin D analog MT19c by altering the A-ring of ergocalciferol. This study describes the therapeutic efficacy and mechanism of action of MT19c in both in vitro and in vivo models. METHODOLOGY/PRINCIPAL FINDING: Antitumor efficacy of MT19c was evaluated in ovarian cancer cell (SKOV-3 xenografts in nude mice and a syngenic rat ovarian cancer model. Serum calcium levels of MT19c or calcitriol treated animals were measured. In-silico molecular docking simulation and a cell based VDR reporter assay revealed MT19c-VDR interaction. Genomewide mRNA analysis of MT19c treated tumors identified drug targets which were verified by immunoblotting and microscopy. Quantification of cellular malonyl CoA was carried out by HPLC-MS. A binding study with PPAR-Y receptor was performed. MT19c reduced ovarian cancer growth in xenograft and syngeneic animal models without causing hypercalcemia or acute toxicity. MT19c is a weak vitamin-D receptor (VDR antagonist that disrupted the interaction between VDR and coactivator SRC2-3. Genome-wide mRNA analysis and western blot and microscopy of MT19c treated xenograft tumors showed inhibition of fatty acid synthase (FASN activity. MT19c reduced cellular levels of malonyl CoA in SKOV-3 cells and inhibited EGFR/phosphoinositol-3kinase (PI-3K activity independently of PPAR-gamma protein. SIGNIFICANCE: Antitumor effects of non-hypercalcemic agent MT19c provide a new approach to the design of vitamin-D based anticancer molecules and a rationale for developing MT19c as a therapeutic agent for malignant ovarian tumors by targeting oncogenic de novo lipogenesis.

  11. [Role of reactive oxygen species in the bactericidal action of quinolones--inhibitors of DNA gyrase].

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    Kotova, V Iu; Mironov, A S; Zavigel'skiĭ, G B

    2014-01-01

    Quinolone antibiotics inhibit DNA gyrase, but the induced degradation of chromosomal DNA is determined by a complex process of joint action quinolones and hydroxyl radical OH'. To quantify the level of stress responses and their time dependence in bacterial cells the induced specific lux-biosensors--the bacterium Escherichia coli, containing hybrid plasmids pColD'::lux; pSoxS'::lux; pKatG'::lux were used in this study. It is shown that quinolones (nalidixic acid, norfloxacin) induce SOS-response and oxidative stress with the formation of superoxide anion O2(-) in E. coli cells. The main parameters of SOS-response and oxidative stress, which depend on the quinolone concentration, are determined. Formation of superoxide anion O2(-) occurs almost simultaneously with the SOS-response. The mutant strain of E. coli sodA sodB, which do not contain active forms of superoxide dismutases SodA and SodB, is characterized by an increased resistance to quinolones as compared to the wild type cells. At high concentrations of quinolones (nalidixic acid-->20 μg/mL; norfloxacin-->500 ng/mL) their bactericidal effect is partially caused by conversion of the superoxide anion to hydrogen peroxide H2O2, conducted by superoxide dismutases SodA and SodB, which is followed by the Fenton reaction and the formation of toxic hydroxyl radical OH'. At low concentrations of quinolones (nalidixic acid--<20 μg/mL; norfloxacin--<500 ng/mL), the role of active oxygen species in the antimicrobial effect is practically nonexistent.

  12. Characterization of quinolone resistance in Salmonella enterica serovar Indiana from chickens in China.

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    Lu, Yan; Zhao, Hongyu; Liu, Yuqi; Zhou, Xuping; Wang, Jinyuan; Liu, Tiantian; Beier, Ross C; Hou, Xiaolin

    2015-03-01

    The aim of this study was to characterize the quinolone resistance of Salmonella enterica serovar Indiana isolated from chickens in China. A total of 293 Salmonella strains were isolated from chicken farms and slaughterhouses in Shandong province of China, and 130 (44.4%) were characterized as Salmonella enterica Indiana (chicken farms, n=52 strains; slaughter houses, n=78 strains). All isolate serotypes were tested with the Kauffmann-White classification system and examined for susceptibility to the quinolones: nalidixic acid, enrofloxacin, norfloxacin, and ciprofloxacin. The resistance of the Salmonella Indiana strains to nalidixic acid, enrofloxacin, norfloxacin, and ciprofloxacin were 100, 73.1, 71.2, and 82.7%, and 100, 59.0, 79.5, and 80.2%, respectively. Selected quinolone resistant strains were evaluated for mutations in genes (gyrA, gyrB, parC, and marA) by DNA sequencing. The gyrA mutation was found in all isolates, the parC mutation was only found in some isolates, and the gyrB and marA mutations were not observed. Quinolone resistance was evaluated in the representative isolates by screening for the quinolone resistance determinants, qnrA, qnrB, qnrS, qepA, and aac (6 ')-Ib-cr using PCR technology. The quinolone resistance determinants in Salmonella, qnrA, qnrB, qnrS, and qepA were negative by PCR, but aac(6 ')-Ib-cr had high detection rates of 90.4 and 96.2% in chicken farms and slaughterhouses, respectively. Salmonella Indiana containing the gyrA mutation was prevalent in farms and slaughterhouses and possessed a high frequency of the quinolone resistance determinant aac(6 ')-Ib-cr. These bacteria may have originated from the same source.

  13. Mechanisms of quinolone resistance and implications for human and animal health

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    Velhner Maja

    2010-01-01

    Full Text Available Quinolone antibiotics have been widely used in human and veterinary medicine. This has caused the development of resistance and difficulties in the treatment of complicated bacterial infections in humans. The resistance to quinolones develops due to chromosome mutations and it can also be transferred by plasmids. The target enzyme for quinolones in Gram-negative bacteria is Gyrasa A, while the target enzyme in Grampositive bacteria is mostly topoisomerase IV. Gyrase A consists of two subunits encoded by genes gyrA and gyrB. The function of the enzyme is to introduce negative super coiling in DNA and therefore is essential for the replication of bacteria. Quinolone resistance develops if point mutations at 83 and/or 87 codon are introduced on gyrA. Establishing a minimal inhibitory concentration (MIC to this group of antimicrobials will reveal possible mutations. Recently it was discovered that quinolone resistance is transmittable by plasmid termed PMQR (plasmid mediated quinolone resistance. The target gene marked qnr encodes a pentapeptide repeat family protein. Pentapeptide repeats form sheets, involved in protein-protein interactions. Qnr protein binds to GyrA protecting the enzyme from the inhibitory effect of ciprofloxacin. The distribution of qnr related resistance is higher in humans than in animals. In poultry, however, this type of resistance is present more than in other animals. Plasmid mediated resistance contributes to the faster spread of quinolone resistance. Proper food handling will significantly contribute to decreasing the risk from infection to which people are exposed. In medical and veterinary laboratories antimicrobial resistance monitoring in clinical and environmental isolates is advised. Since correlation between antibiotics application and antimicrobial resistance is often suggested, antimicrobial use must be under strict control of the authorities both in human and in veterinary medicine. .

  14. Geldanamycin and its anti-cancer activities.

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    Fukuyo, Yayoi; Hunt, Clayton R; Horikoshi, Nobuo

    2010-04-01

    Geldanamycin is a benzoquinone ansamycin antibiotic that manifests anti-cancer activity through the inhibition of HSP90-chaperone function. The HSP90 molecular chaperone is expressed at high levels in a wide variety of human cancers including melanoma, leukemia, and cancers in colon, prostate, lung, and breast. In cancer cells dependent upon mutated and/or over-expressed oncogene proteins, HSP90 is thought to have a critical role in regulating the stability, folding, and activity of HSP90-associated proteins, so-called "client proteins". These client proteins include the growth-stimulating proteins and kinases that support malignant transformation. Recently, oncogenic activating BRAF mutants have been identified in variety of cancers where constitutive activation of the MEK/ERK MAPK signaling pathway is the key for tumorigenesis, and they have been shown to be client proteins for HSP90. Accordingly, HSP90 inhibition can suppress certain cancer-causing client proteins and therefore represents an important therapeutic target. The molecular mechanism underlying the anti-cancer effect of HSP90 inhibition is complicated. Geldanamycin and its derivatives have been shown to induce the depletion of mutationally-activated BRAF through several mechanisms. In this review, we will describe the HSP90-inhibitory mechanism, focusing on recent progress in understanding HSP90 chaperone structure-function relationships, the identification of new HSP90 client proteins and the development of HSP90 inhibitors for clinical applications.

  15. PEGylated Silk Nanoparticles for Anticancer Drug Delivery.

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    Wongpinyochit, Thidarat; Uhlmann, Petra; Urquhart, Andrew J; Seib, F Philipp

    2015-11-09

    Silk has a robust clinical track record and is emerging as a promising biopolymer for drug delivery, including its use as nanomedicine. However, silk-based nanomedicines still require further refinements for full exploitation of their potential; the application of "stealth" design principals is especially necessary to support their evolution. The aim of this study was to develop and examine the potential of PEGylated silk nanoparticles as an anticancer drug delivery system. We first generated B. mori derived silk nanoparticles by driving β-sheet assembly (size 104 ± 1.7 nm, zeta potential -56 ± 5.6 mV) using nanoprecipitation. We then surface grafted polyethylene glycol (PEG) to the fabricated silk nanoparticles and verified the aqueous stability and morphology of the resulting PEGylated silk nanoparticles. We assessed the drug loading and release behavior of these nanoparticles using clinically established and emerging anticancer drugs. Overall, PEGylated silk nanoparticles showed high encapsulation efficiency (>93%) and a pH-dependent release over 14 days. Finally, we demonstrated significant cytotoxicity of drug loaded silk nanoparticles applied as single and combination nanomedicines to human breast cancer cells. In conclusion, these results, taken together with prior silk nanoparticle data, support a viable future for silk-based nanomedicines.

  16. Current developments of coumarin-based anti-cancer agents in medicinal chemistry.

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    Emami, Saeed; Dadashpour, Sakineh

    2015-09-18

    Cancer is one of the leading health hazards and the prominent cause of death in the world. A number of anticancer agents are currently in clinical practice and used for treatment of various kinds of cancers. There is no doubt that the existing arsenal of anticancer agents is insufficient due to the high incidence of side effects and multidrug resistance. In the efforts to develop suitable anticancer drugs, medicinal chemists have focused on coumarin derivatives. Coumarin is a naturally occurring compound and a versatile synthetic scaffold possessing wide spectrum of biological effects including potential anticancer activity. This review article covers the current developments of coumarin-based anticancer agents and also discusses the structure-activity relationship of the most potent compounds.

  17. Exploring the anticancer potential of the bacterial protein azurin

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    Ananda M Chakrabarty

    2016-08-01

    Full Text Available Bacterial proteins and their derivative peptides have emerged as promising anticancer agents. Nowadays they represent a valuable set of candidate drugs with different origins and modes of action. Among these, monomeric cupredoxins, which are metalloproteins involved in the electron transport chain of prokaryotes, have been shown to possess potent anticancer activities. In particular, much attention has been focused on azurin produced by the pathogenic bacterium Pseudomonas aeruginosa. More recently, several in vitro and in vivo studies have reported the multi-targeting anticancer properties of azurin. Moreover, p28, a peptide derived from azurin, has completed two phase I clinical trials in cancer patients with promising results. In this updated review, we examine the current knowledge regarding azurin’s modes of action as an anticancer therapeutic protein. We also review the clinical trial results of p28 emphasizing findings that make it suited (alone or in combination as a therapeutic agent for cancer treatment. Finally we discuss and address the challenges of using the human microbiome to discover novel and unique therapeutic cupredoxin-like proteins.

  18. Anticancer activity of Amauroderma rude.

    Directory of Open Access Journals (Sweden)

    Chunwei Jiao

    Full Text Available More and more medicinal mushrooms have been widely used as a miraculous herb for health promotion, especially by cancer patients. Here we report screening thirteen mushrooms for anti-cancer cell activities in eleven different cell lines. Of the herbal products tested, we found that the extract of Amauroderma rude exerted the highest activity in killing most of these cancer cell lines. Amauroderma rude is a fungus belonging to the Ganodermataceae family. The Amauroderma genus contains approximately 30 species widespread throughout the tropical areas. Since the biological function of Amauroderma rude is unknown, we examined its anti-cancer effect on breast carcinoma cell lines. We compared the anti-cancer activity of Amauroderma rude and Ganoderma lucidum, the most well-known medicinal mushrooms with anti-cancer activity and found that Amauroderma rude had significantly higher activity in killing cancer cells than Ganoderma lucidum. We then examined the effect of Amauroderma rude on breast cancer cells and found that at low concentrations, Amauroderma rude could inhibit cancer cell survival and induce apoptosis. Treated cancer cells also formed fewer and smaller colonies than the untreated cells. When nude mice bearing tumors were injected with Amauroderma rude extract, the tumors grew at a slower rate than the control. Examination of these tumors revealed extensive cell death, decreased proliferation rate as stained by Ki67, and increased apoptosis as stained by TUNEL. Suppression of c-myc expression appeared to be associated with these effects. Taken together, Amauroderma rude represented a powerful medicinal mushroom with anti-cancer activities.

  19. Effect of various storage conditions on the stability of quinolones in raw milk.

    Science.gov (United States)

    Chen, Meixia; Wen, Fang; Wang, Hui; Zheng, Nan; Wang, Jiaqi

    2016-07-01

    Research on the storage stability of antibiotic residues in milk is important for method development or validation, milk quality control and risk assessment during screening, confirmation, qualitative or quantitative analysis. This study was conducted using UPLC-MS/MS to determine the stability of six quinolones - ciprofloxacin (CIP), danofloxacin (DAN), enrofloxacin (ENR), sarafloxacin (SAR), difloxacin (DIF) and flumequine (FLU) - in raw milk stored under various conditions to investigate if quinolones degrade during storage of milk, and finally to determine optimal storage conditions for analysis and scientific risk assessment of quinolone residues in raw milk. The storage conditions included different temperatures and durations (4°C for 4, 8, 24 and 48 h; -20°C for 1, 7 and 30 days; -80°C for 1, 7 and 30 days), thawing temperatures (25, 40 and 60°C), freeze-thaw cycles (1-5), and the addition of different preservatives (sodium thiocyanate, sodium azide, potassium dichromate, bronopol and methanal). Most quinolones exhibited high stability at 4°C for up to 24 h, but began to degrade after 48 h. In addition, no degradation of quinolones was seen when milk samples were stored at -20°C for up to 7 days; however, 30 days of storage at -20°C resulted in a small amount of degradation (about 30%). Similar results were seen when samples were stored at -80°C. Moreover, no losses were observed when frozen milk samples were thawed at 25, 40 or 60°C. All the quinolones of interest, except sarafloxacin, were stable when milk samples were thawed at 40°C once and three times, but unstable after five freeze-thaw cycles. Preservatives affected the stability of quinolones, but the effects differed depending on the preservative and quinolone. The results of this study indicate optimum storage protocols for milk samples, so that residue levels reflect those at the time of initial sample analysis, and should improve surveillance programmes for quinolones in raw milk.

  20. Fluorescence quenching as a tool to investigate quinolone antibiotic interactions with bacterial protein OmpF.

    Science.gov (United States)

    Neves, Patrícia; Sousa, Isabel; Winterhalter, Mathias; Gameiro, Paula

    2009-02-01

    The outer membrane porin OmpF is an important protein for the uptake of antibiotics through the outer membrane of gram-negative bacteria; however, the possible binding sites involved in this uptake are still not recognized. Determination, at the molecular level, of the possible sites of antibiotic interaction is very important, not only to understand their mechanism of action but also to unravel bacterial resistance. Due to the intrinsic OmpF fluorescence, attributed mainly to its tryptophans (Trp(214), Trp(61)), quenching experiments were used to assess the site(s) of interaction of some quinolone antibiotics. OmpF was reconstituted in different organized structures, and the fluorescence quenching results, in the presence of two quenching agents, acrylamide and iodide, certified that acrylamide quenches Trp(61) and iodide Trp(214). Similar data, obtained in presence of the quinolones, revealed distinct behaviors for these antibiotics, with nalidixic acid interacting near Trp(214) and moxifloxacin near Trp(61). These studies, based on straightforward and quick procedures, show the existence of conformational changes in the protein in order to adapt to the different organized structures and to interact with the quinolones. The extent of reorganization of the protein in the presence of the different quinolones allowed an estimate on the sites of protein/quinolone interaction.

  1. The evidence for clonal spreading of quinolone resistance with a particular clonal complex of Campylobacter jejuni.

    Science.gov (United States)

    Kovač, J; Cadež, N; Lušicky, M; Nielsen, E Møller; Ocepek, M; Raspor, P; Možina, S Smole

    2014-12-01

    Campylobacter is the most prevalent cause of bacterial gastroenteritis worldwide and it represents a significant public health risk of increasing severity due to its escalating resistance to clinically important quinolone and macrolide antibiotics. As a zoonotic pathogen Campylobacter is transmitted along the food chain and naturally cycles from environmental waters, feedstuff, animals and food to humans. We determined antibiotic resistance profiles, as well as multilocus sequence types and flaA-SVR types for 52 C. jejuni isolated in Slovenia from human, animal, raw and cured chicken meat and water samples. Twenty-eight different sequence types, arranged in ten clonal complexes, three new allele types and five new sequence types were identified, indicating the relatively high diversity in a small group of strains. The assignment of strains from different sources to the same clonal complexes indicates their transmission along the food supply chain. The most prevalent clonal complex was CC21, which was also the genetic group with 95% of quinolone-resistant strains. Based on the genetic relatedness of these quinolone-resistant strains identified by polymerase chain reaction with a mismatch amplification mutation assay and sequencing of the quinolone resistance-determining region of the gyrA gene, we conclude that the high resistance prevalence observed indicates the local clonal spread of quinolone resistance with CC21.

  2. Introduction of quinolone resistant Escherichia coli to Swedish broiler population by imported breeding animals.

    Science.gov (United States)

    Börjesson, Stefan; Guillard, Thomas; Landén, Annica; Bengtsson, Björn; Nilsson, Oskar

    2016-10-15

    During recent years a rapid increase of quinolone resistant Escherichia coli have been noted in the Swedish broiler population, despite the lack of a known selective pressure. The current study wanted to investigate if imported breeding birds could be a source for the quinolone resistant E. coli. The occurrence of quinolone resistant E. coli was investigated, using selective cultivation with nalidixic acid, in grand-parent birds on arrival to Sweden and their progeny. In addition, sampling in hatcheries and empty cleaned poultry houses was performed. Clonality of isolates was investigated using a 10-loci multiple-locus variable number tandem repeat analysis (MLVA). To identify the genetic basis for the resistance isolates were also analysed for occurrence of plasmid-mediated quinolone resistance (PMQR) determinants and characterization of chromosomal mutations. E. coli resistant to nalidixic acid occurred in grandparent birds imported to Sweden for breeding purposes. Four predominant MLVA types were identified in isolates from grandparent birds, parent birds and broilers. However, resistant E. coli with identical MLVA patterns were also present in hatcheries and poultry houses suggesting that the environment plays a role in the occurrence. Nalidixic acid resistance was due to a mutation in the gyrA gene and no PMQR could be identified. The occurrence of identical clones in all levels of the production pyramid points to that quinolone resistant E. coli can be introduced through imported breeding birds and spread by vertical transmission to all levels of the broiler production pyramid.

  3. Semiempirical MNDO and UV Absorption Studies on Tautomerism of 2-Quinolones

    Science.gov (United States)

    Mirek, Julian; Syguła, Andrzej

    1982-11-01

    Semiempirical MNDO calculations with geometry optimization were carried out for seven 4-X-2-quinolone tautomers (X = H, CH3, Cl, OCH3, N(CH3)2, COOH, COOCH3). The results show that 2-hydroxyquinolines are less stabilized compared to 2-quinoIones than 2-hydroxypyridines vs. 2-pyridones. The earlier estimated correction applied to these MNDO results suggests that 4-X-2-quinolones have lower chemical binding energies than the corresponding 4-X-2- hydroxyquinolines by ca. 2.1-3.3 kcal/mol. It is additionally shown that the substituent in position 4 does not influence significantly the relative stabilities of the tautomers. The results of the calculations are verified by UV absorption studies of diluted decane solutions of 2-quinolones at ca. 120°. CNDO/S-Cl-1 calculations based on the optimal MNDO geometries were carried out for 4-X-2- quinolone tautomers. The results generally agree well with the experimental data. A disagreement of the data for 4-COOR-2-quinolones is rationalized.

  4. Study of the luminescence behavior of seven quinolones on a paper substrate

    Energy Technology Data Exchange (ETDEWEB)

    Li Junfen [Institute of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006 (China)]. E-mail: fenjunli@sina.com; Li Jianqing [Institute of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006 (China); Shuang Shaomin [Institute of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006 (China); Dong Chuan [Institute of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006 (China)]. E-mail: dc@sxu.edu.cn

    2005-08-29

    Studies on the luminescence spectra behaviors of seven quinines on solid substrate (SS-RTP) were performed. Experimental conditions, such as heavy atom type, pH and drying time of the sample, etc. on solid substrate room temperature phosphorescence (SS-RTP) or solid substrate delayed fluorescence (SS-DF), were studied in detail. CdCl{sub 2} could induce strongest RTP or DF emission of these quinolones. In addition, a comparative study on the spectral behavior of seven quinolones was given, including low temperature phosphorescence (LTP), low temperature fluorescence (LTF) and spectra methioned above. New determination methods for the analysis of seven quinolones by solid substrate room temperature fluorescence (SS-RTF), SS-RTP or SS-DF with filter paper as solid substrate were presented. Analytical characteristics of these methods of seven quinolones were studied. The linear dynamic ranges (LDR), the limit of detection (LOD) and the relative standard deviation (R.S.D.) were valued. Recoveries of seven quinolones in human urine samples were from 98.1% to 104.3%.

  5. Protective effect of Qnr on agents other than quinolones that target DNA gyrase.

    Science.gov (United States)

    Jacoby, George A; Corcoran, Marian A; Hooper, David C

    2015-11-01

    Qnr is a plasmid-encoded and chromosomally determined protein that protects DNA gyrase and topoisomerase IV from inhibition by quinolones. Despite its prevalence worldwide and existence prior to the discovery of quinolones, its native function is not known. Other synthetic compounds and natural products also target bacterial topoisomerases. A number were studied as molecular probes to gain insight into how Qnr acts. Qnr blocked inhibition by synthetic compounds with somewhat quinolone-like structure that target the GyrA subunit, such as the 2-pyridone ABT-719, the quinazoline-2,4-dione PD 0305970, and the spiropyrimidinetrione pyrazinyl-alkynyl-tetrahydroquinoline (PAT), indicating that Qnr is not strictly quinolone specific, but Qnr did not protect against GyrA-targeting simocyclinone D8 despite evidence that both simocyclinone D8 and Qnr affect DNA binding to gyrase. Qnr did not affect the activity of tricyclic pyrimidoindole or pyrazolopyridones, synthetic inhibitors of the GyrB subunit, or nonsynthetic GyrB inhibitors, such as coumermycin A1, novobiocin, gyramide A, or microcin B17.Thus, in this set of compounds the protective activity of Qnr was confined to those that, like quinolones, trap gyrase on DNA in cleaved complexes.

  6. System engineering approach to planning anticancer therapies

    CERN Document Server

    Świerniak, Andrzej; Smieja, Jaroslaw; Puszynski, Krzysztof; Psiuk-Maksymowicz, Krzysztof

    2016-01-01

    This book focuses on the analysis of cancer dynamics and the mathematically based synthesis of anticancer therapy. It summarizes the current state-of-the-art in this field and clarifies common misconceptions about mathematical modeling in cancer. Additionally, it encourages closer cooperation between engineers, physicians and mathematicians by showing the clear benefits of this without stating unrealistic goals. Development of therapy protocols is realized from an engineering point of view, such as the search for a solution to a specific control-optimization problem. Since in the case of cancer patients, consecutive measurements providing information about the current state of the disease are not available, the control laws are derived for an open loop structure. Different forms of therapy are incorporated into the models, from chemotherapy and antiangiogenic therapy to immunotherapy and gene therapy, but the class of models introduced is broad enough to incorporate other forms of therapy as well. The book be...

  7. In-silico Design, Synthesis, Anti-inflammatory and Anticancer Evaluation of Pyrazoline Analogues of Vanillin

    Directory of Open Access Journals (Sweden)

    M. J. Neethu

    2014-04-01

    Full Text Available A series of novel pyrazoline derivatives of vanillin were synthesized. The hydroxyl group in vanillin was masked by converting into methyl vanillin. The methyl vanillin was allowed to condense with different acetophenone derivatives gave chalcone derivatives and finally cyclized with thiosemicarbazide to form the pyrazoline derivatives of vanillin. Docking studies were carried out against anti-inflammatory cyclooxygenase receptor and anticancer farnesyl transferase receptor. Majority of the synthesized compounds showed good fitting with the active site of all the docked targets. The synthesized compounds had shown significant anti inflammatory and anticancer activities.

  8. Quinolone and macrolide resistance in Campylobacter jejuni and C-coli: Resistance mechanisms and trends in human isolates

    DEFF Research Database (Denmark)

    Engberg, J.; Aarestrup, Frank Møller; Taylor, D. E.;

    2001-01-01

    The incidence of human Campylobacter jejuni and C. coli infections has increased markedly in many parts of the world in the last decade as has the number of quinolone-resistant and, to a lesser extent, macrolide-resistant Campylobacter strains causing infections. We review macrolide and quinolone...

  9. Metal-free transannulation reaction of indoles with nitrostyrenes: a simple practical synthesis of 3-substituted 2-quinolones.

    Science.gov (United States)

    Aksenov, Alexander V; Smirnov, Alexander N; Aksenov, Nicolai A; Aksenova, Inna V; Frolova, Liliya V; Kornienko, Alexander; Magedov, Igor V; Rubin, Michael

    2013-10-18

    3-Substituted 2-quinolones are obtained via a novel, metal-free transannulation reaction of 2-substituted indoles with 2-nitroalkenes in polyphosphoric acid. The reaction can be used in conjunction with the Fisher indole synthesis offering a practical three-component heteroannulation methodology to produce 2-quinolones from arylhydrazines, 2-nitroalkenes and acetophenone.

  10. [Investigation of plasmid-mediated quinolone resistance genes in quinolone-resistant Escherichia coli and Klebsiella spp. isolates from bloodstream infections].

    Science.gov (United States)

    Buruk, Celal Kurtuluş; Öztel Ocak, Hikmet; Bayramoğlu, Gülçin; Aydın, Faruk

    2016-04-01

    One of the treatment options of Escherichia coli and Klebsiella spp. infections which are the most common opportunistic pathogens of gram-negative sepsis is quinolones. Resistance to quinolones which act by disrupting DNA synthesis has been increasing. Horizontal transfer of plasmid-mediated quinolone resistance (PMQR) genes play an important role in the spread of resistance. The data about the prevalence of PMQR genes in our country is quite limited. The aim of this study was to investigate the presence of known PMQR genes namely qnrA, qnrB, qnrC, qnrS, qnrD, aac(6')-Ib-cr, qepA and oqxAB amongst quinolone-resistant E. coli and Klebsiella spp. strains isolated from blood cultures. One hundred twenty seven E.coli and 66 Klebsiella isolates detected as nalidixic acid- and/or ciprofloxacin-resistant by phenotypical methods, from 193 blood samples of 187 patients admitted to Karadeniz Technical University, Faculty of Medicine, Department of Medical Microbiology, Bacteriology Unit of Patient Service Laboratory between January 2012 to August 2013 were included in the study. The presence of PMQR genes were investigated by polymerase chain reaction (PCR) and for the detection of aac(6')-Ib-cr variants PCR-restriction fragment length polymorphism (PCR-RFLP) method was used. The positive bands were sequenced using the same primers, and aligned with formerly defined resistance gene sequences, and confirmed. In the study, 56.7% (72/127) of E.coli and 19.7% (13/66) of Klebsiella spp. isolates, with a total of 44% (85/193) of all the isolates were found to be phenotypically resistant to quinolones. Of the 13 resistant Klebsiella isolates, 11 were K.pneumoniae, and two were K.oxytoca. Extended-spectrum beta-lactamase (ESBL)-producing isolates showed higher resistance (50/80, 62.5%) to quinolones than the negative ones (35/113, 30.9%). The prevalence of quinolone resistance genes among resistant E. coli and Klebsiella spp. isolates was determined as qnrA, 1.4% and 15.4%; qnrB, 4

  11. Distribution of quinolones, sulfonamides, tetracyclines in aquatic environment and antibiotic resistance in Indochina

    Directory of Open Access Journals (Sweden)

    Satoru eSuzuki

    2012-02-01

    Full Text Available Southeast Asia has become the center of rapid industrial development and economic growth. However, this growth has far outpaced investment in public infrastructure, leading to the unregulated release of many pollutants, including wastewater-related contaminants such as antibiotics. Antibiotics are of major concern because they can easily be released into the environment from numerous sources, and can subsequently induce development of antibiotic-resistant bacteria. Recent studies have shown that for some categories of drugs this source-to-environment antibiotic resistance relationship is more complex. This review summarizes current understanding regarding the presence of quinolones, sulfonamides, and tetracyclines in aquatic environments of Indochina and the prevalence of bacteria resistant to them. Several noteworthy findings are discussed: 1 quinolone contamination and the occurrence of quinolone resistance are not correlated; 2 occurrence of the sul sulfonamide resistance gene varies geographically; and 3 microbial diversity might be related to the rate of oxytetracycline resistance.

  12. Quinolone Resistance among Salmonella enterica from Cattle, Broilers and Swine in Denmark

    DEFF Research Database (Denmark)

    Wiuff, C.; Baggesen, Dorte Lau; Madsen, M.;

    2000-01-01

    This study was conducted to determine the susceptibility to nalidixic acid and fluoroquinolones of Salmonella Dublin, S. Enteritidis, and S. Typhimurium isolates from cattle, broilers, and pigs over time in Denmark and to characterise the gyrA, gyrB, and parC genes in quinolone-resistant isolates...... to quinolones. A single (1.1%) S. Typhimurium isolate from 1995 and three (5.9%) from 1998 were resistant to nalidixic acid. Six (9.0%) S. Dublin isolates from 1996, four (4.2%) from 1997, and one (1.7%) from 1998 were resistant to nalidixic acid. Resistance was not observed among isolates from cattle in 1999...... that quinolone-resistant isolates have emerged in recent years among food-producing animals, especially among S. Enteritidis from broilers in Denmark, and that the resistance mainly is associated with mutations in gyrA....

  13. Occurrence of quinolone- and beta-lactam-resistant Escherichia coli in danish broiler flocks

    DEFF Research Database (Denmark)

    Bortolaia, Valeria; Guardabassi, Luca; Bisgaard, Magne;

    resistant to quinolones or ß-lactams. Sock samples were collected from 10 broiler parent flocks and 10 broiler offspring flocks. Five pairs of socks were collected from each house. Samples were enriched in McConkey broth and streaked on McConkey agar added with nalidixic acid (32 µg/ml), ciprofloxacin (2 µg...... and nalidixic acid resistances were detected in all flocks. The numbers of E. coli resistant to these drugs were higher in plates from parent flocks than in those from offspring flocks. A broiler parent flock without any history of quinolone usage tested positive for ciprofloxacin-resistant E. coli, although......, these types of resistance are widespread in Danish broiler flocks. The observed high prevalence of nalidixic acid-resistant E. coli is surprising since the use of quinolones in poultry is restricted in Denmark. The low prevalence (5%) of flocks positive for ciprofloxacin resistance and the absence...

  14. Plasmid-mediated quinolone resistance; interactions between human, animal and environmental ecologies

    Directory of Open Access Journals (Sweden)

    Laurent ePOIREL

    2012-02-01

    Full Text Available Resistance to quinolones and fluoroquinolones is being increasingly reported among human but also veterinary isolates during the last two to three decades, very likely as a consequence of the large clinical usage of those antibiotics. Even if the principle mechanisms of resistance to quinolones are chromosome-encoded, due to modifications of molecular targets (DNA gyrase and topoisomerase IV, decreased outer-membrane permeability (porin defect and overexpression of naturally-occurring efflux, the emergence of plasmid-mediated quinolone resistance (PMQR has been reported since 1998. Although these PMQR determinants confer low-level resistance to quinolones and/or fluoroquinolones, they are a favorable background for selection of additional chromosome-encoded quinolone resistance mechanisms. Different transferable mechanisms have been identified, corresponding to the production of Qnr proteins, of the aminoglycoside acetyltransferase AAC(6’-Ib-cr, or of the QepA-type or OqxAB-type efflux pumps. Qnr proteins protect target enzymes (DNA gyrase and type IV topoisomerase from quinolone inhibition (mostly nalidixic acid. The AAC(6’-Ib-cr determinant acetylates several fluoroquinolones, such as norfloxacin and ciprofloxacin. Finally, the QepA and OqxAB efflux pumps extrude fluoroquinolones from the bacterial cell. A series of studies have identified the environment to be a reservoir of PMQR genes, with farm animals and aquatic habitats being significantly involved. In addition, the origin of the qnr genes has been identified, corresponding to the waterborne species Shewanella sp. Altogether, the recent observations suggest that the aquatic environment might constitute the original source of PMQR genes, that would secondly spread among animal or human isolates.

  15. Characterization of Salmonella Typhimurium DNA gyrase as a target of quinolones.

    Science.gov (United States)

    Kongsoi, Siriporn; Yokoyama, Kazumasa; Suprasert, Apinun; Utrarachkij, Fuangfa; Nakajima, Chie; Suthienkul, Orasa; Suzuki, Yasuhiko

    2015-08-01

    Quinolones exhibit good antibacterial activity against Salmonella spp. isolates and are often the choice of treatment for life-threatening salmonellosis due to multi-drug resistant strains. To assess the properties of quinolones, we performed an in vitro assay to study the antibacterial activities of quinolones against recombinant DNA gyrase. We expressed the S. Typhimurium DNA gyrase A (GyrA) and B (GyrB) subunits in Escherichia coli. GyrA and GyrB were obtained at high purity (>95%) by nickel-nitrilotriacetic acid agarose resin column chromatography as His-tagged 97-kDa and 89-kDa proteins, respectively. Both subunits were shown to reconstitute an ATP-dependent DNA supercoiling activity. Drug concentrations that suppressed DNA supercoiling by 50% (IC50 s) or generated DNA cleavage by 25% (CC25 s) demonstrated that quinolones highly active against S. Typhimurium DNA gyrase share a fluorine atom at C-6. The relationships between the minimum inhibitory concentrations (MICs), IC50 s and CC25 s were assessed by estimating a linear regression between two components. MICs measured against S. Typhimurium NBRC 13245 correlated better with IC50 s (R = 0.9988) than CC25 s (R = 0.9685). These findings suggest that the DNA supercoiling inhibition assay may be a useful screening test to identify quinolones with promising activity against S. Typhimurium. The quinolone structure-activity relationship demonstrated here shows that C-8, the C-7 ring, the C-6 fluorine, and N-1 cyclopropyl substituents are desirable structural features in targeting S. Typhimurium gyrase.

  16. [Bactericidal activity of sitafloxacin and other new quinolones against antimicrobial resistant Streptococcus pneumoniae].

    Science.gov (United States)

    Kobayashi, Intetsu; Kanayama, Akiko; Hasegawa, Miyuki; Kaneko, Akihiro

    2013-02-01

    We conducted a study assess the bactericidal activity of sitafloxacin (STFX) against Streptococcus pneumoniae isolates recovered from respiratory infections including penicillin-resistant (PRSP) isolates, macrolide resistant isolates possessing mefA and ermB resistance genes and quinolone resistance isolates with mutations in gyrA or gyrA and parC. Each isolate tested was grown in hemosupplemented Mueller-Hinton broth and adjusted to approximately 10(5) CFU/ mL. Isolates were than exposed to a Cmax antimicrobial blood level that would be attained with routine antimicrobial administration and an antimicrobial level that would be expected 4 hours post-Cmax (Cmax 4hr). Bactericidal activity was measured for up to 8 hours. Excluding a subset of S. pneumoniae isolates with mutations in the quinolone resistance determining region (QRDR), all quinolones showed bactericidal activity at Cmax and Cmax 4 hr antimicrobial concentrations for up to 8 hours. Against S. pneumoniae isolates with either gyrA or gyrA and parC mutations, bactericidal activity of STFX was shown for up to 4 to 8 hours following Cmax based on a limit of detection of quinolones tested where adjusted to concentrations corresponding to their MICs, STFX showed the most rapid bactericidal activity against PRSP. This rapid bactericidal activity in PRSP is a key to the effectiveness of STFX. Our findings show that beyond inhibition of bacterial replication by blocking their DNA replication pathway and synthesis of proteins, STFX demonstrated characteristics contributing to greater bactericidal activity compared to GRNX. In conclusion, of the newer quinolones, STFX showed the strongest bactericidal activity against S. pneumoniae isolates with mutations in the QRDR which indicates that it may show the most effective clinical utility among the quinolones in respiratory infections.

  17. Macrolides vs. quinolones for community-acquired pneumonia: meta-analysis of randomized controlled trials.

    Science.gov (United States)

    Skalsky, K; Yahav, D; Lador, A; Eliakim-Raz, N; Leibovici, L; Paul, M

    2013-04-01

    The relative efficacy, safety and ecological implications of macrolides vs. quinolones in the treatment of community-acquired pneumonia (CAP) are debatable. We performed a systematic review and meta-analysis of randomized controlled trials comparing any macrolide vs. any quinolone for the treatment of CAP among adult inpatients or outpatients, as monotherapy or both in combination with a beta-lactam. We did not limit inclusion by pneumonia severity, publication status, language or date of publication. The primary outcomes assessed were 30-day all-cause mortality and treatment failure. Two authors independently extracted the data. Fixed effect meta-analysis of risk ratios (RRs) with 95% confidence intervals was performed. Sixteen trials (4989 patients) fulfilling inclusion criteria were identified, mostly assessing outpatients with mild to moderate CAP. All-cause mortality was not significantly different for macrolides vs. quinolones, RR 1.03 (0.63-1.68, seven trials), with a low event rate (2%). Treatment failure was significantly lower with quinolones, RR 0.78 (0.67-0.91, 16 trials). The definition of failure used in the primary studies was not clearly representative of patients' benefit. Microbiological failure was lower with quinolones, RR 0.63 (0.49-0.81, 13 trials). All adverse events, adverse events requiring discontinuation and any premature antibiotic discontinuation were significantly more frequent with macrolides, mainly on account of gastrointestinal adverse events. Resistance development was not assessed in the trials. Randomized controlled trials show an advantage of quinolones in the treatment of CAP with regard to clinical cure without need for antibiotic modification at end of treatment and gastrointestinal adverse events. The clinical significance of this advantage is unclear.

  18. Structural requirements of 3-carboxyl-4(1H)-quinolones as potential antimalarials from 2D and 3D QSAR analysis.

    Science.gov (United States)

    Li, Jiazhong; Li, Shuyan; Bai, Chongliang; Liu, Huanxiang; Gramatica, Paola

    2013-07-01

    Malaria is a fatal tropical and subtropical disease caused by the protozoal species Plasmodium. Many commonly available antimalarial drugs and therapies are becoming ineffective because of the emergence of multidrug resistant Plasmodium falciparum, which drives the need for the development of new antimalarial drugs. Recently, a series of 3-carboxyl-4(1H)-quinolone analogs, derived from the famous compound endochin, were reported as promising candidates for orally efficacious antimalarials. In this study, to analyze the structure-activity relationships (SAR) of these quinolones and investigate the structural requirements for antimalarial activity, the 2D multiple linear regressions (MLR) method and 3D comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) methods are employed to evolve different QSAR models. All these models give satisfactory results with highly accurate fitting and strong external predictive abilities for chemicals not used in model development. Furthermore, the contour maps from 3D models can provide an intuitive understanding of the key structure features responsible for the antimalarial activities. In conclusion, we summarize the detailed position-specific structural requirements of these derivatives accordingly. All these results are helpful for the rational design of new compounds with higher antimalarial bioactivities.

  19. Anticancer molecular mechanisms of resveratrol

    Directory of Open Access Journals (Sweden)

    Elena Maria Varoni

    2016-04-01

    Full Text Available Resveratrol is a pleiotropic phytochemical belonging to the stilbene family. Despite it is only significantly present in grape products, a huge amount of preclinical studies investigated its anticancer properties in a plethora of cellular and animal models. Molecular mechanisms of resveratrol involved signaling pathways related to: extracellular growth factors and receptor tyrosine kinases; formation of multiprotein complexes and cell metabolism; cell proliferation and genome instability; cytoplasmic tyrosine kinase signaling (cytokine, integrin and developmental pathways; signal transduction by the transforming growth factor-β super-family; apoptosis and inflammation; immune-surveillance and hormone signaling. Resveratrol also showed a promising role to counteract multi-drug resistance: in adjuvant therapy, associated with 5-fluoruracyl and cisplatin, resveratrol had additive and/or synergistic effects increasing the chemosensitization of cancer cells. Resveratrol, by acting on diverse mechanisms simultaneously, has been emphasized as a promising, multi-target, anticancer agent, relevant in both cancer prevention and treatment.

  20. Improving quinolone use in hospitals by using a bundle of interventions in an interrupted time series analysis.

    Science.gov (United States)

    Willemsen, Ina; Cooper, Ben; van Buitenen, Carin; Winters, Marjolein; Andriesse, Gunnar; Kluytmans, Jan

    2010-09-01

    The objectives of the present study were to determine the effects of multiple targeted interventions on the level of use of quinolones and the observed rates of resistance to quinolones in Escherichia coli isolates from hospitalized patients. A bundle consisting of four interventions to improve the use of quinolones was implemented. The outcome was measured from the monthly levels of use of intravenous (i.v.) and oral quinolones and the susceptibility patterns for E. coli isolates from hospitalized patients. Statistical analyses were performed using segmented regression analysis and segmented Poisson regression models. Before the bundle was implemented, the annual use of quinolones was 2.7 defined daily doses (DDDs)/100 patient days. After the interventions, in 2007, this was reduced to 1.7 DDDs/100 patient days. The first intervention, a switch from i.v. to oral medication, was associated with a stepwise reduction in i.v. quinolone use of 71 prescribed daily doses (PDDs) per month (95% confidence interval [CI] = 47 to 95 PDDs/month, P quinolones (reduction, 107 PDDs/month [95% CI = 58 to 156 PDDs/month). Before the interventions the quinolone resistance rate was increasing, on average, by 4.6% (95% CI = 2.6 to 6.1%) per year. This increase leveled off, which was associated with intervention 2 and intervention 4, active monitoring of prescriptions and feedback. Trends in resistance to other antimicrobial agents did not change. This study showed that the hospital-wide use of quinolones can be significantly reduced by an active policy consisting of multiple interventions. There was also a stepwise reduction in the rate of quinolone resistance associated with the bundle of interventions.

  1. Synthesis, characterization and anticancer studies of Ni(II), Pd(II) and Pt(II) complexes with Schiff base derived from N-methylhydrazinecarbothioamide and 2-hydroxy-5-methoxy-3-nitrobenzaldehyde

    Science.gov (United States)

    Arafath, Md. Azharul; Adam, Farook; Razali, Mohd. R.; Ahmed Hassan, Loiy E.; Ahamed, Mohamed B. Khadeer; Majid, Amin Malik S. A.

    2017-02-01

    A carbothioamide NSO tridentate Schiff base ligand (HL) and its square planar complexes Na[NiLOAc], Na[PdLOAc] and [PtLdmso] have been synthesized and characterized on the basis of melting point, elemental analysis, FT-IR, 1H NMR, 13C NMR, UV-Vis spectra. The structure of HL was elucidated with X-ray diffraction analysis. In the present study, the synthesized compounds were evaluated for their anticancer properties against three human cancer cell lines breast cancer (MCF-7), cervical (Hela), and colon (HCT-116). In addition, the cytotoxicity of the synthesized compounds was tested on a normal human cell line (human endothelial cell line EA.hy926). Among the tested compounds, the complex [NiLOAc] excelled in halting proliferation of the cervical and colon cancer cells with median inhibitory concentration (IC50) values of 28.33 and 34.4 μM, respectively. The complex, [PdLOAc] demonstrated selective cytotoxicity against breast cancer line MCF-7 with IC50 = 47.5 μM, while HL showed inhibitory effect against colon cancer cell line (HCT-116) with IC50 = 55.66 μM. The complex, [PtLdmso] showed mild activity against breast cancer (MCF-7) and cervical cancer (Hela) cells with IC50 = 64.44 and 68.3 μM, respectively, whereas, it displayed insignificant cytotoxicity against human endothelial cells (EA.hy926) with IC50 > 200 μM. Cancer cells treated with [NiLOAc] showed apoptotic features such as membrane blebbing and DNA condensation. Thus, the findings of the present study demonstrated that the series of metal complexes of HL could form the new lead for development of cancer chemotherapies to treat human cervical, breast and colon malignancies.

  2. Severe pneumococcal pneumonia: impact of new quinolones on prognosis

    Directory of Open Access Journals (Sweden)

    Meybeck Agnes

    2011-03-01

    Full Text Available Abstract Background Most guidelines have been proposing, for more than 15 years, a β-lactam combined with either a quinolone or a macrolide as empirical, first-line therapy of severe community acquired pneumonia (CAP requiring ICU admission. Our goal was to evaluate the outcome of patients with severe CAP, focusing on the impact of new rather than old fluoroquinolones combined with β-lactam in the empirical antimicrobial treatments. Methods Retrospective study of consecutive patients admitted in a 16-bed general intensive care unit (ICU, between January 1996 and January 2009, for severe (Pneumonia Severity Index > or = 4 community-acquired pneumonia due to non penicillin-resistant Streptococcus pneumoniae and treated with a β-lactam combined with a fluoroquinolone. Results We included 70 patients of whom 38 received a β-lactam combined with ofloxacin or ciprofloxacin and 32 combined with levofloxacin. Twenty six patients (37.1% died in the ICU. Three independent factors associated with decreased survival in ICU were identified: septic shock on ICU admission (AOR = 10.6; 95% CI 2.87-39.3; p = 0.0004, age > 70 yrs. (AOR = 4.88; 95% CI 1.41-16.9; p = 0.01 and initial treatment with a β-lactam combined with ofloxacin or ciprofloxacin (AOR = 4.1; 95% CI 1.13-15.13; p = 0.03. Conclusion Our results suggest that, when combined to a β-lactam, levofloxacin is associated with lower mortality than ofloxacin or ciprofloxacin in severe pneumococcal community-acquired pneumonia.

  3. Assessing T-cell responses in anticancer immunotherapy

    Science.gov (United States)

    Escors, David; Liechtenstein, Therese; Perez-Janices, Noemi; Schwarze, Julia; Dufait, Ines; Goyvaerts, Cleo; Lanna, Alessio; Arce, Frederick; Blanco-Luquin, Idoia; Kochan, Grazyna; Guerrero-Setas, David; Breckpot, Karine

    2013-01-01

    Since dendritic cells operate as professional antigen-presenting cells (APCs) and hence are capable of jumpstarting the immune system, they have been exploited to develop a variety of immunotherapeutic regimens against cancer. In the few past years, myeloid-derived suppressor cells (MDSCs) have been shown to mediate robust immunosuppressive functions, thereby inhibiting tumor-targeting immune responses. Thus, we propose that the immunomodulatory activity of MDSCs should be carefully considered for the development of efficient anticancer immunotherapies. PMID:24244902

  4. Antidiabetic and anticancer activities of Mangifera indica cv. Okrong leaves

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    Aunyachulee Ganogpichayagrai

    2017-01-01

    Full Text Available Diabetes and cancer are a major global public health problem. Plant-derived agents with undesirable side-effects were required. This study aimed to evaluate antidiabetic and anticancer activities of the ethanolic leaf extract of Mangifera indica cv. Okrong and its active phytochemical compound, mangiferin. Antidiabetic activities against yeast α-glucosidase and rat intestinal α-glucosidase were determined using 1 mM of p-nitrophenyl-α-D-glucopyranoside as substrate. Inhibitory activity against porcine pancreatic α-amylase was performed using 1 mM of 2-chloro-4 nitrophenol-α-D-maltotroside-3 as substrate. Nitrophenol product was spectrophotometrically measured at 405 nm. Anticancer activity was evaluated against five human cancer cell lines compared to two human normal cell lines using 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide assay. Mango leaf extract and mangiferin exhibited dose-dependent inhibition against yeast α-glucosidase with the IC 50 of 0.0503 and 0.5813 mg/ml, respectively, against rat α-glucosidase with the IC 50 of 1.4528 and 0.4333 mg/ml, respectively, compared to acarbose with the IC 50 of 11.9285 and 0.4493 mg/ml, respectively. For anticancer activity, mango leaf extract, at ≥200 μg/ml showed cytotoxic potential against all tested cancer cell lines. In conclusion, mango leaf possessed antidiabetic and anticancer potential in vitro.

  5. Novel application of Wiener vis-à-vis Szeged indices: Antitubercular activities of quinolones

    Indian Academy of Sciences (India)

    Vijay K Agarwal; Shahnaz Bano; Keshav C Mathur; Padmakar V Khadikar

    2000-04-01

    The paper gives a brief account of the recently introduced Szeged index (Sz). Using this index antitubercular activities of N-2,4-difluorophenyl quinolones are subjected to quantitative structure-activity relationship analysis. The potential of Sz related to the Wiener index (W) is critically discussed. In addition, Huckel molecular orbital energies: HOMO, LUMO and total were also used for comparing and modelling antitubercular activities of the quinolones. The results, based on univariate as well as multivariate regressions, have shown that W, Sz and total give better results and that the correlations improve in multivariate regression analyses.

  6. Prevalence of plasmid-mediated quinolone resistance determinants among oxyiminocephalosporin-resistant Enterobacteriaceae in Argentina

    Directory of Open Access Journals (Sweden)

    Giovanna Rincon Cruz

    2013-11-01

    Full Text Available High quinolone resistance rates were observed among oxyiminocephalosporin-resistant enterobacteria. In the present study, we searched for the prevalence of plasmid-mediated quinolone resistance (PMQR genes within the 55 oxyiminocephalosporin-resistant enterobacteria collected in a previous survey. The main PMQR determinants were aac(6'-Ib-cr and qnrB, which had prevalence rates of 42.4% and 33.3%, respectively. The aac(6'-Ib-cr gene was more frequently found in CTX-M-15-producing isolates, while qnrB was homogeneously distributed among all CTX-M producers.

  7. Anticancer and cancer preventive properties of marine polysaccharides: some results and prospects.

    Science.gov (United States)

    Fedorov, Sergey N; Ermakova, Svetlana P; Zvyagintseva, Tatyana N; Stonik, Valentin A

    2013-12-02

    Many marine-derived polysaccharides and their analogues have been reported as showing anticancer and cancer preventive properties. These compounds demonstrate interesting activities and special modes of action, differing from each other in both structure and toxicity profile. Herein, literature data concerning anticancer and cancer preventive marine polysaccharides are reviewed. The structural diversity, the biological activities, and the molecular mechanisms of their action are discussed.

  8. [Studies on quinolone antibacterials. I. Synthesis and antibacterial activity of 7-(2-aminoethoxy)-, 7-(2-aminoethylthio)-, and 7-(2-aminoethylamino)-1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo qui noline -3-carboxylic acids and their derivatives].

    Science.gov (United States)

    Yoshida, T; Yamamoto, Y; Yagi, N; Yasuda, S; Katoh, H; Itoh, Y

    1990-04-01

    7-(2-Aminoethoxy)-, 7-(2-aminoethylthio)-, and 7-(2-aminoethylamino)-1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxoq uin oline-3- carboxylic acids and their derivatives (11a--f, h, j, k, 12a--f, and 13a--f) were synthesized and their antibacterial activities were tested. Among them, compounds (13a, d) having a primary amino group at the terminal position of alkoxy and alkylthio groups were found to have excellent in vitro and in vivo antibacterial activity comparable to those of ciprofloxacin (5). Structure-activity relationship of these compounds was also stated.

  9. In vitro and in vivo Methods for Anticancer Activity Evaluation and Some Indian Medicinal Plants Possessing Anticancer Properties: An Overview

    Directory of Open Access Journals (Sweden)

    Sumitra Chanda

    2013-07-01

    Full Text Available Cancer is a major public health burden in both developed and developing countries. Anticancer activity is the effect of natural and synthetic or biological and chemical agents to reverse, suppress or prevent carcinogenic progression. Several synthetic agents are used to cure the disease but they have their toxicity and hence the research is going on to investigate the plant derived chemotherapeutic agents. Therefore an attempt has been made to review different in vitro and in vivo methods for estimating anticancer properties of natural products from medicinal plants. In this review, 50 anticancer medicinal plants of Indian origin belonging to 35 families are reported along with detailed information regarding part used, extract used, type of the model used, types of tested cancer cell lines, etc. These plants continue to be used against various types of tumours such as sarcoma, lymphoma, carcinoma and leukemia. All these plants are potential candidates for in vivo studies since they are showing good in vitro anticancer activity.

  10. Nickel-quinolones interaction. Part 5-Biological evaluation of nickel(II) complexes with first-, second- and third-generation quinolones.

    Science.gov (United States)

    Skyrianou, Kalliopi C; Perdih, Franc; Papadopoulos, Athanasios N; Turel, Iztok; Kessissoglou, Dimitris P; Psomas, George

    2011-10-01

    The nickel(II) complexes with the quinolone antibacterial agents oxolinic acid, flumequine, enrofloxacin and sparfloxacin in the presence of the N,N'-donor heterocyclic ligand 2,2'-bipyridylamine have been synthesized and characterized. The quinolones act as bidentate ligands coordinated to Ni(II) ion through the pyridone oxygen and a carboxylato oxygen. The crystal structure of [(2,2'-bipyridylamine)bis(sparfloxacinato)nickel(II)] has been determined by X-ray crystallography. UV study of the interaction of the complexes with calf-thymus DNA (CT DNA) has shown that they bind to CT DNA with [(2,2'-bipyridylamine)bis(flumequinato)nickel(II)] exhibiting the highest binding constant to CT DNA. The cyclic voltammograms of the complexes have shown that in the presence of CT DNA the complexes can bind to CT DNA by the intercalative binding mode which has also been verified by DNA solution viscosity measurements. Competitive study with ethidium bromide (EB) has shown that the complexes can displace the DNA-bound EB indicating that they bind to DNA in strong competition with EB. The complexes exhibit good binding propensity to human or bovine serum albumin protein having relatively high binding constant values. The biological properties of the [Ni(quinolonato)(2)(2,2'-bipyridylamine)] complexes have been evaluated in comparison to the previously reported Ni(II) quinolone complexes [Ni(quinolonato)(2)(H(2)O)(2)], [Ni(quinolonato)(2)(2,2'-bipyridine)] and [Ni(quinolonato)(2)(1,10-phenanthroline)]. The quinolones and their Ni(II) complexes have been tested for their antioxidant and free radical scavenging activity. They have been also tested in vitro for their inhibitory activity against soybean lipoxygenase.

  11. Prevalence of quinolone resistance mechanisms and associations to minimum inhibitory concentrations in quinolone-resistant Escherichia coli isolated from humans and swine in Denmark.

    Science.gov (United States)

    Cavaco, Lina Maria; Frimodt-Møller, Niels; Hasman, Henrik; Guardabassi, Luca; Nielsen, Lene; Aarestrup, Frank Møller

    2008-06-01

    Prevalence of quinolone resistance mechanisms and associations to minimum inhibitory concentrations (MICs) of nalidixic acid (NAL) and ciprofloxacin (CIP) were investigated in 124 Escherichia coli isolated from humans (n=85) and swine (n=39) in Denmark. The collection included 59 high-level CIP-resistant isolates (MIC >or= 4) from human (n=51) and pig origin (n=8) and 65 low-level CIP-resistant isolates (MIC >or= 0.125) from human (n=34) and pig origin (n=31). Resistance by target modification was screened by PCR amplification and sequencing of the quinolone resistance determining regions (QRDRs) of gyrA, gyrB, parC, and parE. QRDR mutations occurred in all except two isolates (98%). All high-level CIP-resistant E. coli had one or two mutations in gyrA in combination with mutations in parC or parE. Mutations in parC and parE were only found in combination with gyrA mutations, and no mutations were observed in gyrB. Efflux pump mechanisms were detected in 10 human (11.8%) and 29 porcine (74.4%) isolates by an efflux pump inhibitor (EPI) agar dilution assay. The aac(6')-Ib-cr gene mediating resistance by enzymatic modification was found in 12 high-level CIP-resistant human isolates. The qnrA and qnrS genes conferring quinolone resistance by target protection were detected in two human low-level CIP-resistant isolates that did not display NAL resistance. As expected, target mutation in QRDRs was the most prevalent mechanism of quinolone resistance. This mechanism was complemented by efflux mechanisms in most porcine isolates. Transferable resistance by target protection or enzymatic modification was less common (10%) and restricted to human isolates.

  12. SYNTHESIS OF NEW TWO DERIVATIVES OF 6-MERCAPTOPURINE (6MP 6-[5-PYRIDINE-4-YL- 1, 2, 3, 4-OXADIAZOLE-2-YLDITHIOL]-9H-PURINE (38 AND 9H-PURINE-6-YL-BENYLDITHIOCARBAMATE (45 WITH CYTOTOXICITY RESULTS FROM THE NATIONAL CANCER INSTITUTE'S ANTICANCER DRUG SCREEN

    Directory of Open Access Journals (Sweden)

    Mohammed Hassan Mohammed et al

    2012-08-01

    Full Text Available 6-[(5-pyridine-yl-1, 2, 3, 4-oxadiazole-2-yldithiol]-9H-purine (38 and 9H-purine-6yl-benzyldithiocarbamate (45 are synthesized as possible prodrugs for 6-mercaptopurine(6-MP. The generation of the compounds 38, 42, 45 and 48 were accomplished following multistep reaction procedures. The reaction and purity of the products were checked by TLC, the structure of the final compounds and their intermediates were confirmed by their melting points, infra red spectroscopy and whether differences elemental microanalysis. To determine exist among in sensitivity different tissue types toward treatment with 38 and 45. The cytotoxicity of the two compounds and their intermediates were confirmed by their melting points, infra red spectroscopy and elemental microanalysis. The cytotoxicity of two derivatives (38 and 45 was assessed in National Cancer Institute's anticancer screening program, and the results were compared with the cytotoxicity of 6-MP obtained in the same screen. The results show that the compound 38 and 45 were more cytotoxic than 6-MP. Additionally the prodrugs are less effective against leukemia cell line than 6-MP. Both derivatives exhibited high growth-inhibitory activities in renal cell line. However, compound 45 is more cytotoxic than 38 against ovarian cell line.

  13. The inactivation of RNase G reduces the Stenotrophomonas maltophilia susceptibility to quinolones by triggering the heat shock response.

    Directory of Open Access Journals (Sweden)

    Alejandra eBernardini

    2015-10-01

    Full Text Available Quinolone resistance is usually due to mutations in the genes encoding bacterial topoisomerases. However different reports have shown that neither clinical quinolone resistant isolates nor in vitro obtained S. maltophilia mutants present mutations in such genes. The mechanisms so far described consist on efflux pumps' overexpression. Our objective is to get information on novel mechanisms of S. maltophilia quinolone resistance. For this purpose, a transposon-insertion mutant library was obtained in S. maltophilia D457.. One mutant presenting reduced susceptibility to nalidixic acid was selected. Inverse PCR showed that the inactivated gene encodes RNase G. Complementation of the mutant with wild-type RNase G allele restored the susceptibility to quinolones. Transcriptomic and real-time RT-PCR analyses showed that several genes encoding heat-shock response proteins were expressed at higher levels in the RNase defective mutant than in the wild-type strain. In agreement with this situation, heat-shock reduces the S. maltophilia susceptibility to quinolone. We can then conclude that the inactivation of the RNase G reduces the susceptibility of S. maltophilia to quinolones, most likely by regulating the expression of heat-shock response genes. Heat-shock induces a transient phenotype of quinolone resistance in S. maltophilia.

  14. [Preliminary study on occurrence and health risk assessment of quinolone antibiotics in vegetables from Guangzhou, China].

    Science.gov (United States)

    Li, Yan-Wen; Zhang, Yan; Mo, Ce-Hui; Tai, Yi-Ping; Wu, Xiao-Lian; Wang, Ji-Yang; Su, Qing-Yun

    2010-10-01

    Quinolone antibiotics (QNs) including norfloxacin (NOR), enrofolxacin (ENR), ciprofloxacin (CIP) and lomefloxacin (LOM) in vegetable samples collected from Guangzhou were determined by high performance liquid chromatography (HPLC) coupled with fluorescent detector (FLD). The detected frequency of QNs was 96% in vegetables. The total concentration of quinolones (sigma QNs) detected in vegetable ranged from 1.0 microg/kg to 1 683.1 microg/kg (F.W.). Leafy vegetable topped the content of quinolones among the three types of vegetables, followed by the melon-fruit vegetable and rhizome vegetable. The detected frequency of the four quinolone antibiotics ranked as NOR > CIP > LOM > ENR. Except ENR, concentrations of CIP, NOR, LOM and sigma QNs in pollution-free vegetable, green vegetable and organic vegetable were higher than those in routine cultivated vegetables. The maximum contribution to ADI value (caculated by the sum of CIP and ENR) is estimated up to 41.5% and 83% for adults and children respectively via consumption of vegetables.

  15. Improved microbial screning assay for the detection of quinolone residues in poultry and eggs

    NARCIS (Netherlands)

    Pikkemaat, M.G.; Mulder, P.P.J.; Elferink, J.W.A.; Cocq, A.; Nielen, M.W.F.; Egmond, van H.J.

    2007-01-01

    An improved microbiological screening assay is reported for the detection of quinolone residues in poultry muscle and eggs. The method was validated using fortified tissue samples and is the first microbial assay to effectively detect enrofloxacin, difloxacin, danofloxacin, as well as flumequine and

  16. Quinolone therapy of Klebsiella pneumoniae sepsis following irradiation: Comparison of pefloxacin, ciprofloxacin, and ofloxacin

    Energy Technology Data Exchange (ETDEWEB)

    Brook, I.; Elliott, T.B.; Ledney, G.D. (Armed Forces Radiobiology Research Institute, Bethesda, MD (USA))

    1990-05-01

    Exposure to whole-body irradiation is associated with fatal gram-negative sepsis. The effect of oral therapy with three quinolones, pefloxacin, ciprofloxacin, and ofloxacin, for orally acquired Klebsiella pneumoniae infection was tested in B6D2F1 mice exposed to 8.0 Gy whole-body irradiation from bilaterally positioned 60Co sources. A dose of 10(8) organisms was given orally 2 days after irradiation, and therapy was started 1 day later. Quinolones reduced colonization of the ileum with K. pneumoniae: 16 of 28 (57%) untreated mice harbored the organisms, compared to only 12 of 90 (13%) mice treated with quinolones (P less than 0.005). K. pneumoniae was isolated from the livers of 6 of 28 untreated mice, compared to only 1 of 90 treated mice (P less than 0.001). Only 5 of 20 (25%) untreated mice survived for at least 30 days compared with 17 of 20 (85%) mice treated with ofloxacin, 15 of 20 (75%) mice treated with pefloxacin, and 14 of 20 (70%) treated with ciprofloxacin (P less than 0.05). These data illustrate the efficacy of quinolones for oral therapy of orally acquired K. pneumoniae infection in irradiated hosts.

  17. Prevalence and characteristics of quinolone resistance in Escherichia coli in veal calves

    NARCIS (Netherlands)

    Hordijk, J.; Veldman, K.T.; Dierikx, C.M.; Essen-Zandbergen, van A.; Wagenaar, J.A.; Mevius, D.J.

    2012-01-01

    Quinolone resistance is studied and reported increasingly in isolates from humans, food-producing animals and companion animals. Resistance can be caused by chromosomal mutations in topoisomerase genes, plasmid-mediated resistance genes, and active transport through efflux pumps. Cross sectional dat

  18. Plasmid-mediated quinolone resistance among non-typhi Salmonella enterica isolates, USA

    Science.gov (United States)

    We determined the prevalence of plasmid-mediated quinolone resistance mechanisms among non-Typhi Salmonella (NTS) spp. isolates from humans, food animals, and retail meat in the United States in 2007. Fifty-one (2.4%) of human isolates (n=2165), 5 (1.6%) of isolates from animal isolates (n=1915) an...

  19. Generation and characterization of quinolone-specific DNA aptamers suitable for water monitoring.

    Science.gov (United States)

    Reinemann, C; Freiin von Fritsch, U; Rudolph, S; Strehlitz, B

    2016-03-15

    Quinolones are antibiotics that are accredited in human and veterinary medicine but are regularly used in high quantities also in industrial livestock farming. Since these compounds are often only incompletely metabolized, significant amounts contaminate the aquatic environment and negatively impact on a variety of different ecosystems. Although there is increasing awareness of problems caused by pharmaceutical pollution, available methods for the detection and elimination of numerous pharmaceutical residues are currently inefficient or expensive. While this also applies to antibiotics that may lead to multi-drug resistance in pathogenic bacteria, aptamer-based technologies potentially offer alternative approaches for sensitive and efficient monitoring of pharmaceutical micropollutants. Using the Capture-SELEX procedure, we here describe the selection of an aptamer pool with enhanced binding qualities for fluoroquinolones, a widely used group of antibiotics in both human and veterinary medicine. The selected aptamers were shown to detect various quinolones with high specificity, while specific binding activities to structurally unrelated drugs were not detectable. The quinolone-specific aptamers bound to ofloxacin, one of the most frequently prescribed fluoroquinolone, with high affinity (KD=0.1-56.9 nM). The functionality of quinolone-specific aptamers in real water samples was demonstrated in local tap water and in effluents of sewage plants. Together, our data suggest that these aptamers may be applicable as molecular receptors in biosensors or as catcher molecules in filter systems for improved monitoring and treatment of polluted water.

  20. [Determination of 25 quinolones in cosmetics by liquid chromatography-tandem mass spectrometry].

    Science.gov (United States)

    Lin, Li; Zhang, Yi; Tu, Xiaoke; Xie, Liqi; Yue, Zhenfeng; Kang, Haining; Wu, Weidong; Luo, Yao

    2015-03-01

    An analytical method was developed for the simultaneous determination of 25 quinolones, including danofloxacin mesylate, enrofloxacin, flumequine, oxloinic acid, ciprofloxacin, sarafloxacin, nalidixic acid, norfloxacin, and ofloxacin etc in cosmetics using direct extraction and liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). Cosmetic sample was extracted by acidified acetonitrile, defatted by n-hexane and separated on Poroshell EC-C18 column with gradient elution program using acetonitrile and water (both containing 0. 1% formic acid) as the mobile phases and analyzed by LC-ESI-MS/MS under the positive mode using multiple reaction monitoring (MRM). The interference of matrix was reduced by the matrix-matched calibration standard curve. The method showed good linearities over the range of 1-200 mg/kg for the 25 quinolones with good linear correlation coefficients (r ≥ 0.999). The method detection limit of the 25 quinolones was 1.0 mg/kg, and the recoveries of all analytes in lotion, milky and cream cosmetics matrices ranged from 87.4% to 105% at the spiked levels of 1, 5 and 10 mg/kg with the relative standard deviations (RSD) of 4.54%-19.7% (n = 6). The results indicated that this method is simple, fast and credible, and suitable for the simultaneous determination of the quinolones in the above three types of cosmetics.

  1. Synthesis and preliminary cytotoxic evaluation of substituted indoles as potential anticancer agents

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A variety of indole derivatives were designed, synthesized and preliminarily evaluated for their in vitro cytotoxic activity in the A431 and H460 cell lines. All the compounds examined conferred unusual potency in a tumor cell cytotoxicity assay. The findings showed the indole derivatives would be a promising candidate for the development of new anticancer agents.

  2. A series of 2D metal-quinolone complexes: Syntheses, structures, and physical properties

    Energy Technology Data Exchange (ETDEWEB)

    He, Jiang-Hong [College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China); Xiao, Dong-Rong, E-mail: xiaodr98@yahoo.com.cn [College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China); Chen, Hai-Yan; Sun, Dian-Zhen; Yan, Shi-Wei; Wang, Xin; Ye, Zhong-Li [College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China); Luo, Qun-Li, E-mail: qlluo@swu.edu.cn [College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China); Wang, En-Bo, E-mail: wangeb889@nenu.edu.cn [Key Laboratory of Polyoxometalate Science of Ministry of Education, Department of Chemistry, Northeast Normal University, Changchun 130024 (China)

    2013-02-15

    Six novel 2D metal-quinolone complexes, namely [Cd(cfH)(bpdc)]{center_dot}H{sub 2}O (1), [M(norfH)(bpdc)]{center_dot}H{sub 2}O (M=Cd (2) and Mn (3)), [Mn{sub 2}(cfH)(odpa)(H{sub 2}O){sub 3}]{center_dot}0.5H{sub 2}O (4), [Co{sub 2}(norfH)(bpta)({mu}{sub 2}-H{sub 2}O)(H{sub 2}O){sub 2}]{center_dot}H{sub 2}O (5) and [Co{sub 3}(saraH){sub 2}(Hbpta){sub 2}(H{sub 2}O){sub 4}]{center_dot}9H{sub 2}O (6) (cfH=ciprofloxacin, norfH=norfloxacin, saraH=sarafloxacin, bpdc=4,4 Prime -biphenyldicarboxylate, odpa=4,4 Prime -oxydiphthalate, bpta=3,3 Prime ,4,4 Prime -biphenyltetracarboxylate) have been synthesized and characterized. Compounds 1-3 consist of 2D arm-shaped layers based on the 1D {l_brace}M(COO){r_brace}{sub n}{sup n+} chains. Compounds 4 and 5 display 2D structures based on tetranuclear manganese or cobalt clusters with (3,6)-connected kgd topology. Compound 6 exhibits a 2D bilayer structure, which represents the first example of metal-quinolone complexes with 2D bilayer structure. By inspection of the structures of 1-6, it is believed that the long aromatic polycarboxylate ligands are important for the formation of 2D metal-quinolone complexes. The magnetic properties of compounds 3-6 was studied, indicating the existence of antiferromagnetic interactions. Furthermore, the luminescent properties of compounds 1-2 are discussed. - Graphical abstract: Six novel 2D metal-quinolone complexes have been prepared by self-assemblies of the quinolones and metal salts in the presence of long aromatic polycarboxylates. Highlights: Black-Right-Pointing-Pointer Compounds 1-3 consist of novel 2D arm-shaped layers based on the 1D {l_brace}M(COO){r_brace}{sub n}{sup n+} chains. Black-Right-Pointing-Pointer Compounds 4 and 5 are two novel 2D layers based on tetranuclear Mn or Co clusters with kgd topology. Black-Right-Pointing-Pointer Compound 6 is the first example of metal-quinolone complexes with 2D bilayer structure. Black-Right-Pointing-Pointer Compounds 1-6 represent six unusual

  3. Microbial screening for quinolones residues in cow milk by bio-optical method.

    Science.gov (United States)

    Appicciafuoco, Brunella; Dragone, Roberto; Frazzoli, Chiara; Bolzoni, Giuseppe; Mantovani, Alberto; Ferrini, Anna Maria

    2015-03-15

    The use of antibiotics on lactating cows should be monitored for the possible risk of milk contamination with residues. Accordingly, Maximum Residue Levels (MRLs) are established by the European Commission to guarantee consumers safety. As pointed out by Dec 2002/657/EC, screening is the first step in the strategy for antibiotic residue control, thus playing a key role in the whole control procedure. However, current routine screening methods applied in milk chain still fail to detect residues of quinolones at concentrations of interest. This paper reports the findings of a new bio-optical method for the screening of quinolones residues in bovine milk, based on E. coli ATCC 11303 growth inhibition. The effect of blank and spiked cow milk samples (aliquots equivalents to 0.8%, v/v) is evaluated in Mueller Hinton Broth (MHb) and MHb enriched with MgSO4 2% (MHb-Mg) inoculated with the test strain at the concentration of 10(4)CFU/mL. The presence of quinolones inhibits the cellular growth in MHb, while this effect is neutralized in MHb-Mg allowing both detection and presumptive identification of quinolones. Growth of the test strain is monitored at 37 °C in a Bioscreen C automated system, and Optical Density (OD) at 600 nm is recorded every 10 min after shaking for 10s. Growth curves (OD vs. time) of E. coli ATCC 11303 are assessed in milk samples, with and without quinolones, and their differences in terms of ΔOD (ΔOD600nm=ODMHb-Mg-ODMHb) are calculated. The presence of quinolones is detected by the cellular growth inhibition (OD vs time, none increase in the value OD) and presumptively identified through the increase of the slope of ΔOD600nm curve (ΔOD vs. time), after about 3h of incubation. The detection limit for ciprofloxacin and enrofloxacin is at the level of MRL, for marbofloxacin is at 2-fold the MRL whereas for danofloxacin is at 4-fold the MRL. Although the sensitivity of the method could be further improved and the procedure automated, it is a

  4. Sub-inhibitory concentrations of vancomycin prevent quinolone-resistance in a penicillin-resistant isolate of Streptococcus pneumoniae

    Directory of Open Access Journals (Sweden)

    Moreillon Philippe

    2001-07-01

    Full Text Available Abstract Background The continuous spread of penicillin-resistant pneumococci represents a permanent threat in the treatment of pneumococcal infections, especially when strains show additional resistance to quinolones. The main objective of this study was to determine a treatment modality impeding the emergence of quinolone resistance. Results Exposure of a penicillin-resistant pneumococcus to increasing concentrations of trovafloxacin or ciprofloxacin selected for mutants resistant to these drugs. In the presence of sub-inhibitory concentrations of vancomycin, development of trovafloxacin-resistance and high-level ciprofloxacin-resistance were prevented. Conclusions Considering the risk of quinolone-resistance in pneumococci, the observation might be of clinical importance.

  5. Mechanistic study of electrochemical oxidation of o-dihydroxybenzenes in the presence of 4-hydroxy-1-methyl-2(1H)-quinolone

    Energy Technology Data Exchange (ETDEWEB)

    Moghaddam, Abdolmajid Bayandori [Department of Medicinal Chemistry, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran 1983963113 (Iran, Islamic Republic of)]. E-mail: bayandori@gmail.com; Kobarfard, Farzad [Department of Medicinal Chemistry, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran 1983963113 (Iran, Islamic Republic of); Fakhari, Ali Reza [Department of Chemistry, Faculty of Science, University of Shahid Beheshti, Tehran (Iran, Islamic Republic of); Nematollahi, Davood [Department of Chemistry, Faculty of Science, University of Bu-Ali-Sina, Hamadan (Iran, Islamic Republic of); Davarani, Saied Saeed Hosseiny [Department of Chemistry, Faculty of Science, University of Shahid Beheshti, Tehran (Iran, Islamic Republic of)

    2005-11-01

    Electrochemical oxidation of o-dihydroxybenzenes (1a and 1b) has been studied in the presence of 4-hydroxy-1-methyl-2(1H)-quinolone (3) as a nucleophile in aqueous solution using cyclic voltammetry and controlled-potential coulometry. The results indicate that the o-quinones derived from o-dihydroxybenzenes (1a and 1b) participate in 1,4-(michael) addition reactions with 3 to form the corresponding new o-dihydroxybenzene derivatives (6a and 6b). We propose a mechanism for the electrode process. The efficient electrochemical synthesis of 6a and 6b has been successfully performed at carbon rod electrodes in an undivided cell in good yield and purity. The products have been characterized after purification by IR, {sup 1}H NMR, {sup 13}C NMR and MS.

  6. Mechanistic study of electrochemical oxidation of catechols in the presence of 4-hydroxy-1-methyl-2(1H)-quinolone

    Energy Technology Data Exchange (ETDEWEB)

    Fakhari, Ali Reza [Department of Chemistry, Faculty of Science, University of Shahid Beheshti, Tehran 19835389 (Iran, Islamic Republic of)]. E-mail: a-zavareh@sbu.ac.ir; Nematollahi, Davood [Department of Chemistry, Faculty of Science, University of Bu-Ali-Sina, Hamadan (Iran, Islamic Republic of); Moghaddam, Abdolmajid Bayandori [Department of Chemistry, Faculty of Science, University of Shahid Beheshti, Tehran 19835389 (Iran, Islamic Republic of)

    2005-09-20

    Electrochemical oxidation of catechols (1a-1c) has been studied in the presence of 4-hydroxy-1-methyl-2(1H)-quinolone (3) as a nucleophile in aqueous solution using cyclic voltammetry and controlled-potential coulometry. The results indicate that the quinones derived from catechols (1a-1c) participate in Michael addition reactions with 3 to form the corresponding benzofuran (or isochromeno[4,3-c]quinoline) derivatives (6a-6c). The electrochemical synthesis of (6a-6c) has been successfully performed in an undivided cell in good yield and purity. The oxidation mechanism was deduced from voltammetric data and by coulometry at controlled-potential. The products have been characterized after purification by IR, {sup 1}H NMR, {sup 13}C NMR and MS.

  7. Detection of quinolones in poultry meat obtained from retail centers in Santiago Province, the Dominican Republic.

    Science.gov (United States)

    Silfrany, R O; Caba, R E; Solís de Los Santos, F; Hanning, I

    2013-02-01

    In the Dominican Republic, poultry consumption per capita is greater than 34 kg of poultry meat per year. However, antibiotics, specifically the quinolone group, may be overused and can result in residues in the poultry meat. These residues are of concern because consumers may have allergies to antibiotics and antibiotic-resistant bacteria can develop from overuse of antibiotics in production. Little is known concerning this issue specifically for Santiago Province in the Dominican Republic. Thus, the main purpose of this research was to evaluate the incidence of residual quinolones in poultry meat and determine whether any residues detected were higher than the residue maximum limits (100 μg/kg) established by food industry authorities, including the U.S. Food and Drug Administration and European Food Safety Authority. A total of 135 samples of chicken breast were taken from different retail meat centers in the nine municipalities of Santiago Province (Santiago, Tamboril, Sabana Iglesia, Villa Bisonó, Puñal, Villa González, Licey, Jánico, and San José De Las Matas) and were analyzed using the Equinox test (Immunotec, Swanton, VT). Of the 135 samples analyzed, 50% from Sabana Iglesia, 20% from Licey, 20% from San Jose De Las Matas, and 6.25% from Santiago contained residues of quinolones higher than the residue maximum limits. No quinolone residues were detected in samples obtained from Janico, Punal, Tamboril, Villa Bisono, or Villa Gonzalez. The results of this investigation suggest that some poultry meat sold for human consumption in Santiago Province of the Dominican Republic contains quinolone residues and may represent a health risk to some consumers.

  8. Decay mechanisms of protonated 4-quinolone antibiotics after electrospray ionization and ion activation.

    Science.gov (United States)

    Kovačević, Borislav; Schorr, Pascal; Qi, Yulin; Volmer, Dietrich A

    2014-11-01

    This study presents a detailed experimental investigation of charge isomers of protonated 4-quinolone antibiotics molecules formed during electrospray ionization (ESI) with proposed dissociation mechanisms after collisional activation. Piperazinyl quinolones have been previously shown to exhibit erratic behavior during tandem MS analyses of biological samples, which originated from varying ratios of two isomeric variants formed during ESI. Here, a combination of ESI-collision-induced dissociation (CID), differential ion mobility spectrometry (DMS), high resolution MS, and density functional theory (DFT) was used to investigate the underlying mechanisms of isomer formation and their individual dissociation behaviors. The study focused on ciprofloxacin; major findings were confirmed using structurally related 4-quinolones. DFT calculations showed a reversal of basicity for piperazinyl quinolones between liquid and gas phase. We provide an experimental comparison and theoretical treatment of factors influencing the formation ratio of the charge isomers during ESI, including solvent pH, protic/aprotic nature of solvent, and structural effects such as pK a and proton affinity. The actual dissociation mechanisms of the isomers of the protonated molecules were studied by separating the individual isomers via DMS-MS, which allowed type-specific CID spectra to be recorded. Both primary CID reactions of the two charge isomers originated from the same carboxyl group by charge-remote (CO(2) loss) and charge-mediated (H(2)O loss) fragmentation of the piperazinyl quinolones, depending on whether the proton resides on the more basic keto or the piperazinyl group, followed by a number of secondary dissociation reactions. The proposed mechanisms were supported by calculated energies of precursors, transition states, and products for competing pathways.

  9. Advances in chalcones with anticancer activities.

    Science.gov (United States)

    Karthikeyan, Chandrabose; Moorthy, Narayana S H Narayana; Ramasamy, Sakthivel; Vanam, Uma; Manivannan, Elangovan; Karunagaran, Devarajan; Trivedi, Piyush

    2015-01-01

    Chalcones are naturally occurring compounds exhibiting broad spectrum biological activities including anticancer activity through multiple mechanisms. Literature on anticancer chalcones highlights the employment of three pronged strategies, namely; structural manipulation of both aryl rings, replacement of aryl rings with heteroaryl scaffolds, molecular hybridization through conjugation with other pharmacologically interesting scaffolds for enhancement of anticancer properties. Methoxy substitutions on both the aryl rings (A and B) of the chalcones, depending upon their positions in the aryl rings appear to influence anticancer and other activities. Similarly, heterocyclic rings either as ring A or B in chalcones, also influence the anticancer activity shown by this class of compounds. Hybrid chalcones formulated by chemically linking chalcones to other prominent anticancer scaffolds such as pyrrol[2,1-c][1,4]benzodiazepines, benzothiazoles, imidazolones have demonstrated synergistic or additive pharmacological activities. The successful application of these three pronged strategies for discovering novel anticancer agents based on chalcone scaffold has resulted in many novel and chemically diverse chalcones with potential therapeutic application for many types of cancer. This review summarizes the concerted efforts expended on the design and development of anticancer chalcones recorded in recent literature and also provides an overview of the patents published in this area between 2007 and 2014 (WO2013022951, WO201201745 & US2012029489).

  10. Clinical pharmacology of novel anticancer drug formulations

    NARCIS (Netherlands)

    Stuurman, F.E.

    2013-01-01

    Studies outlined in this thesis describe the impact of drug formulations on pharmacology of anticancer drugs. It consists of four parts and starts with a review describing the mechanisms of low oral bioavailability of anti-cancer drugs and strategies for improvement of the bioavailability. The major

  11. 喹诺酮类药物的研究进展%Progress on the Research of Pharmaceuticals of Quinolones

    Institute of Scientific and Technical Information of China (English)

    曾焕君; 王怀生

    2014-01-01

    Quinolones are synthetic antibacterial agents. many quinolones have one or two chiral centers and some of enantiomers show dif erent feature in pharmacology, toxicology and pharmacodynamics. In this paper, chiral separation and determination of quinolones about recent years were reviewed for providing some reference in the research of quinolones.%喹诺酮类药物是人工合成的抗菌药,很多药物都具有1~2个手性中心,且有些对映体呈现不同的药理学的、毒理学的、药效学的特性。本文对近几年喹诺酮类的药物手性的拆分与定量进行了研究,为临床上研究喹诺酮类的药物提供了一系列参考依据。

  12. Prevalence of plasmid-mediated quinolone resistance determinants in Enterobacteriaceae strains isolated in North-East Italy.

    Science.gov (United States)

    Kocsis, B; Mazzariol, A; Kocsis, E; Koncan, R; Fontana, R; Cornaglia, G

    2013-02-01

    We investigated the prevalence of plasmid-mediated quinolone resistance genes in 756 clinical isolates of Enterobacteriaceae originating from Microbiology Diagnostic Laboratories of North-East Italy. Five point zero two percent of isolates carried a qnr determinant while the aac(6')-Ib-cr determinant was detected in 9·25% of isolates. We also investigated the association between the plasmid-mediated quinolone resistance and the beta-lactamase genes, and characterized the plasmids carrying these determinants of resistance.

  13. Impact of the E540V amino acid substitution in GyrB of Mycobacterium tuberculosis on quinolone resistance.

    Science.gov (United States)

    Kim, Hyun; Nakajima, Chie; Yokoyama, Kazumasa; Rahim, Zeaur; Kim, Youn Uck; Oguri, Hiroki; Suzuki, Yasuhiko

    2011-08-01

    Amino acid substitutions conferring resistance to quinolones in Mycobacterium tuberculosis have generally been found within the quinolone resistance-determining regions (QRDRs) in the A subunit of DNA gyrase (GyrA) rather than the B subunit of DNA gyrase (GyrB). To clarify the contribution of an amino acid substitution, E540V, in GyrB to quinolone resistance in M. tuberculosis, we expressed recombinant DNA gyrases in Escherichia coli and characterized them in vitro. Wild-type and GyrB-E540V DNA gyrases were reconstituted in vitro by mixing recombinant GyrA and GyrB. Correlation between the amino acid substitution and quinolone resistance was assessed by the ATP-dependent DNA supercoiling assay, quinolone-inhibited supercoiling assay, and DNA cleavage assay. The 50% inhibitory concentrations of eight quinolones against DNA gyrases bearing the E540V amino acid substitution in GyrB were 2.5- to 36-fold higher than those against the wild-type enzyme. Similarly, the 25% maximum DNA cleavage concentrations were 1.5- to 14-fold higher for the E540V gyrase than for the wild-type enzyme. We further demonstrated that the E540V amino acid substitution influenced the interaction between DNA gyrase and the substituent(s) at R-7, R-8, or both in quinolone structures. This is the first detailed study of the contribution of the E540V amino acid substitution in GyrB to quinolone resistance in M. tuberculosis.

  14. The anticancer activity of propolis

    Directory of Open Access Journals (Sweden)

    Jacek Nikliński

    2012-04-01

    Full Text Available Propolis and its compounds have been the subject of many studies due to their antimicrobial and antiinflammatory activity; however, it is now known that they also possess antitumor properties. This review aims to summarize the results of studies on the mechanism of activity of propolis and its active compounds such as CAPE and chrysin in the apoptotic process, and their influence on the proliferation of cancer cells. Our review shows that propolis and its presented compounds induce apoptosis pathways in cancer cells. The antiproliferative effects of propolis, CAPE or chrysin in cancer cells are the result of the suppression of complexes of cyclins, as well as cell cycle arrest. The results of in vitro and in vivo studies suggest that propolis, CAPE and chrysin may inhibit tumor cell progression and may be useful as potential chemotherapeutic or chemopreventive anticancer drugs.

  15. [Anticancer propaganda: myth or reality?].

    Science.gov (United States)

    Demin, E V; Merabishvili, V M

    2014-01-01

    The authors raise a very important problem of anticancer propaganda aimed at the early detection of cancer to be solved nowadays by means of screening and constructive interaction between oncologists and the public. To increase the level of knowledge of the population in this area it is necessary to expand the range of its adequate awareness of tumor diseases. Only joint efforts can limit the destructive effect of cancer on people's minds, so that every person would be responsible for his own health, clearly understanding the advantages of early visit to a doctor. This once again highlights the need of educational work with the public, motivational nature of which allows strengthening the value of screening in the whole complex of measures to fight cancer.

  16. Bacteriocins as potential anticancer agents

    Directory of Open Access Journals (Sweden)

    Sukhraj eKaur

    2015-11-01

    Full Text Available Cancer remains one of the leading causes of deaths worldwide, despite advances in its treatment and detection. The conventional chemotherapeutic agents used for the treatment of cancer have nonspecific toxicity towards normal body cells that cause various side effects. Secondly, cancer cells are known to develop chemotherapy resistance in due course of treatment. Thus, the demand for novel anti-cancer agents is increasing day by day. Some of the experimental studies have reported the therapeutic potential of bacteriocins against various types of cancer cell lines. Bacteriocins are ribosomally-synthesized cationic peptides secreted by almost all groups of bacteria. Some bacteriocins have shown selective cytotoxicity towards cancer cells as compared to normal cells. This makes them promising candidates for further investigation and clinical trials. In this review article, we present the overview of the various cancer cell-specific cytotoxic bacteriocins, their mode of action and efficacies.

  17. Comparative Analysis of Quinolone Resistance in Clinical Isolates of Klebsiella pneumoniae and Escherichia coli from Chinese Children and Adults

    Directory of Open Access Journals (Sweden)

    Ying Huang

    2015-01-01

    Full Text Available The objective of this study was to compare quinolone resistance and gyrA mutations in clinical isolates of Klebsiella pneumoniae and Escherichia coli from Chinese adults who used quinolone in the preceding month and children without any known history of quinolone administration. The antimicrobial susceptibilities of 61 isolates from children and 79 isolates from adults were determined. The mutations in the quinolone resistance-determining regions in gyrA gene were detected by PCR and DNA sequencing. Fluoroquinolone resistance and types of gyrA mutations in isolates from children and adults were compared and statistically analyzed. No significant differences were detected in the resistance rates of ciprofloxacin and levofloxacin between children and adults among isolates of the two species (all P>0.05. The double mutation Ser83→Leu + Asp87→Asn in the ciprofloxacin-resistant isolates occurred in 73.7% isolates from the children and 67.9% from the adults, respectively (P=0.5444. Children with no known history of quinolone administration were found to carry fluoroquinolone-resistant Enterobacteriaceae isolates. The occurrence of ciprofloxacin resistance and the major types of gyrA mutations in the isolates from the children were similar to those from adults. The results indicate that precautions should be taken on environmental issues resulting from widespread transmission of quinolone resistance.

  18. Comparative analysis of quinolone resistance in clinical isolates of Klebsiella pneumoniae and Escherichia coli from Chinese children and adults.

    Science.gov (United States)

    Huang, Ying; Ogutu, James O; Gu, Jiarui; Ding, Fengshu; You, Yuhong; Huo, Yan; Zhao, Hong; Li, Wenjing; Zhang, Zhiwei; Zhang, Wenli; Chen, Xiaobei; Fu, Yingmei; Zhang, Fengmin

    2015-01-01

    The objective of this study was to compare quinolone resistance and gyrA mutations in clinical isolates of Klebsiella pneumoniae and Escherichia coli from Chinese adults who used quinolone in the preceding month and children without any known history of quinolone administration. The antimicrobial susceptibilities of 61 isolates from children and 79 isolates from adults were determined. The mutations in the quinolone resistance-determining regions in gyrA gene were detected by PCR and DNA sequencing. Fluoroquinolone resistance and types of gyrA mutations in isolates from children and adults were compared and statistically analyzed. No significant differences were detected in the resistance rates of ciprofloxacin and levofloxacin between children and adults among isolates of the two species (all P > 0.05). The double mutation Ser83→Leu + Asp87→Asn in the ciprofloxacin-resistant isolates occurred in 73.7% isolates from the children and 67.9% from the adults, respectively (P = 0.5444). Children with no known history of quinolone administration were found to carry fluoroquinolone-resistant Enterobacteriaceae isolates. The occurrence of ciprofloxacin resistance and the major types of gyrA mutations in the isolates from the children were similar to those from adults. The results indicate that precautions should be taken on environmental issues resulting from widespread transmission of quinolone resistance.

  19. Prevalence of quinolone resistance determinants in non-typhoidal Salmonella isolates from human origin in Extremadura, Spain.

    Science.gov (United States)

    Campos, Maria Jorge; Palomo, Gonzalo; Hormeño, Lorena; Herrera-León, Silvia; Domínguez, Lucas; Vadillo, Santiago; Píriz, Segundo; Quesada, Alberto

    2014-05-01

    Resistance to the quinolones nalidixic acid (NAL) and ciprofloxacin (CIP) and the occurrence of quinolone resistance determinants have been investigated in 300 non-typhoidal Salmonella from human origin, isolated in the years between 2004 and 2008, in 6 hospitals within Extremadura (Spain). Salmonella Enteritidis was the major serotype found among quinolone-resistant isolates, most of which were clustered by clonal analysis to a single clone, which presented D87 or S83 substitutions in GyrA. Eleven isolates presented the non-classical quinolone resistance phenotype (resistance to CIP and susceptibility to NAL), lacking mutations in the quinolone resistance determinant region of topoisomerase genes. Among them, one Salmonella Typhimurium isolate carried a qnrS1 gene in a low-molecular-weight plasmid, pQnrS1-HLR25, identical to plasmids previously found in the UK, Taiwan, and USA. The occurrence of this genetic element could represent a risk for the horizontal transmission of quinolone resistance among Enterobacteriaceae in the Iberian Peninsula.

  20. Anticancer Activity of Polyether Ionophore-Salinomycin.

    Science.gov (United States)

    Antoszczak, Michał; Huczyński, Adam

    2015-01-01

    Since the discovery of unusual anti-tumor activity of natural polyether antibiotic - Salinomycin, this compound, along with its derivatives, has been intensively studied against different human cancer cells, both in vivo and in vitro. Salinomycin has shown strong inhibition activity against the proliferation process of many different cancer cells, including multi-drug resistance (MDR) cancer cells, as well as cancer stem cells (CSCs), i.e. leukemic stem cells, colon carcinoma stem cells, prostate cancer stem cells and many others. Additionally, the application of Salinomycin has been proved to enhance the anti-cancer effect of radio- and chemotherapy. Preliminary clinical studies have shown tumor regression and only transient acute side effects after application of Salinomycin. Up to now, major efforts have been devoted to elucidate the biological mechanisms of anti-tumor activity of Salinomycin and it is expected that the results may provide new therapeutic strategies based on biological modulation of Salinomycin activity. This review is focused on and describes the possible role of Salinomycin in cancer therapy and gives an overview of its properties.

  1. NSAIDs: Old Drugs Reveal New Anticancer Targets

    Directory of Open Access Journals (Sweden)

    Gary A. Piazza

    2010-05-01

    Full Text Available There is compelling evidence that nonsteroidal anti-inflammatory drugs (NSAIDs and cyclooxygenase-2 selective inhibitors have antineoplastic activity, but toxicity from cyclooxygenase (COX inhibition and the suppression of physiologically important prostaglandins limits their use for cancer chemoprevention. Previous studies as reviewed here suggest that the mechanism for their anticancer properties does not require COX inhibition, but instead involves an off-target effect. In support of this possibility, recent molecular modeling studies have shown that the NSAID sulindac can be chemically modified to selectively design out its COX-1 and COX-2 inhibitory activity. Unexpectedly, certain derivatives that were synthesized based on in silico modeling displayed increased potency to inhibit tumor cell growth. Other experiments have shown that sulindac can inhibit phosphodiesterase to increase intracellular cyclic GMP levels and that this activity is closely associated with its ability to selectively induce apoptosis of tumor cells. Together, these studies suggest that COX-independent mechanisms can be targeted to develop safer and more efficacious drugs for cancer chemoprevention.

  2. Microfluidics: Emerging prospects for anti-cancer drug screening.

    Science.gov (United States)

    Wlodkowic, Donald; Darzynkiewicz, Zbigniew

    2010-11-10

    Cancer constitutes a heterogenic cellular system with a high level of spatio-temporal complexity. Recent discoveries by systems biologists have provided emerging evidence that cellular responses to anti-cancer modalities are stochastic in nature. To uncover the intricacies of cell-to-cell variability and its relevance to cancer therapy, new analytical screening technologies are needed. The last decade has brought forth spectacular innovations in the field of cytometry and single cell cytomics, opening new avenues for systems oncology and high-throughput real-time drug screening routines. The up-and-coming microfluidic Lab-on-a-Chip (LOC) technology and micro-total analysis systems (μTAS) are arguably the most promising platforms to address the inherent complexity of cellular systems with massive experimental parallelization and 4D analysis on a single cell level. The vast miniaturization of LOC systems and multiplexing enables innovative strategies to reduce drug screening expenditures while increasing throughput and content of information from a given sample. Small cell numbers and operational reagent volumes are sufficient for microfluidic analyzers and, as such, they enable next generation high-throughput and high-content screening of anti-cancer drugs on patient-derived specimens. Herein we highlight the selected advancements in this emerging field of bioengineering, and provide a snapshot of developments with relevance to anti-cancer drug screening routines.

  3. Plasmid-related quinolone resistance determinants in epidemic Vibrio parahaemolyticus, uropathogenic Escherichia coli, and marine bacteria from an aquaculture area in Chile.

    Science.gov (United States)

    Aedo, Sandra; Ivanova, Larisa; Tomova, Alexandra; Cabello, Felipe C

    2014-08-01

    Marine bacteria from aquaculture areas with industrial use of quinolones have the potential to pass quinolone resistance genes to animal and human pathogens. The VPA0095 gene, related to the quinolone resistance determinant qnrA, from clinical isolates of epidemic Vibrio parahaemolyticus conferred reduced susceptibility to quinolone after cloning into Escherichia coli K-12 either when acting alone or synergistically with DNA gyrase mutations. In addition, a plasmid-mediated quinolone resistance gene from marine bacteria, aac(6')-Ib-cr, was identical to aac(6')-Ib-cr from urinary tract isolates of E. coli, suggesting a recent flow of this gene between these bacteria isolated from different environments. aac(6')-Ib-cr from E. coli also conferred reduced susceptibility to quinolone and kanamycin when cloned into E. coli K-12.

  4. 1,2-substituted 4-(1H)-quinolones: synthesis, antimalarial and antitrypanosomal activities in vitro.

    Science.gov (United States)

    Wube, Abraham; Hüfner, Antje; Seebacher, Werner; Kaiser, Marcel; Brun, Reto; Bauer, Rudolf; Bucar, Franz

    2014-09-10

    A diverse array of 4-(1H)-quinolone derivatives bearing substituents at positions 1 and 2 were synthesized and evaluated for antiprotozoal activities against Plasmodium falciparum and Trypanosoma brucei rhodesiense, and cytotoxicity against L-6 cells in vitro. Furthermore, selectivity indices were also determined for both parasites. All compounds tested showed antimalarial activity at low micromolar concentrations, with varied degrees of selectivity against L-6 cells. Compound 5a was found to be the most active against P. falciparum, with an IC50 value of 90 nM and good selectivity for the malarial parasite compared to the L-6 cells. Compound 10a, on the other hand, showed a strong antitrypanosomal effect with an IC50 value of 1.25 µM. In this study side chain diversity was explored by varying the side chain length and substitution pattern on the aliphatic group at position-2 and a structure-antiprotozoal activity study revealed that the aromatic ring introduced at C-2 contributed significantly to the antiprotozoal activities.

  5. Determination of fluorinated quinolone antibacterials by ion chromatography with fluorescence detection

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yan-zhen; ZHANG Zheng-yi; ZHOU Yan-chun; LIU Li; ZHU Yan

    2007-01-01

    For preparing fluorinated quinolone antibiotic medicine locally used in stomatology, simultaneous determination of norfloxacin, ciprofloxacin, and enoxacin was carried out by multiphase ion chromatography with fluorescence detection. Quinolone antibiotics were separated by Dionex OmniPac PAX-500 column with an eluent of 15 mmol/L H2SO4 and 35% methanol (v/v) at a flow-rate of 1.0 ml/min and detected with fluorescence with excitation and emission wave lengths of 347 nm and 420 nm respectively. The detection limits (S/N=3) ofnorfloxacin, ciprofloxacin and enoxacin were 50, 105 and 80 ng/ml respectively. The relative standard deviations of retention time, peak area and peak height were less than 1.1% and good linear relationship resulted.The developed method was applied to pharmaceutical formulations and biological fluids.

  6. Origins of the Quinolone Class of Antibacterials: An Expanded "Discovery Story".

    Science.gov (United States)

    Bisacchi, Gregory S

    2015-06-25

    Published descriptions of the specific lines of research leading to the discovery of therapeutically important medicines, especially major new class medicines, have long provided value to the biopharmaceutical community as models of success, often influencing the strategies and methods of subsequent drug research. Quinolone antibacterials represent one of medicine's most important classes of anti-infective agents; yet in contrast to many other classes of anti-infectives, astonishingly few details concerning the origin of the class or the rationale leading to the selection of the first clinical agent, nalidixic acid, were ever published by the discoverers. Moreover, earlier disclosures of an independent discovery of the quinolone class of antibacterials have been almost entirely overlooked by the scientific literature. This review brings together all the available information from primary literature sources relating to both discoveries and provides for the first time a much fuller, if still partially speculative, story of the earliest years of this important class of drugs.

  7. 4(1H)-Quinolones with liver stage activity against Plasmodium berghei.

    Science.gov (United States)

    Lacrue, Alexis N; Sáenz, Fabián E; Cross, R Matthew; Udenze, Kenneth O; Monastyrskyi, Andrii; Stein, Steven; Mutka, Tina S; Manetsch, Roman; Kyle, Dennis E

    2013-01-01

    With the exception of primaquine, tafenoquine, and atovaquone, there are very few antimalarials that target liver stage parasites. In this study, a transgenic Plasmodium berghei parasite (1052Cl1; PbGFP-Luc(con)) that expresses luciferase was used to assess the anti-liver stage parasite activity of ICI 56,780, a 7-(2-phenoxyethoxy)-4(1H)-quinolone (PEQ), as well as two 3-phenyl-4(1H)-quinolones (P4Q), P4Q-146 and P4Q-158, by using bioluminescent imaging (BLI). Results showed that all of the compounds were active against liver stage parasites; however, ICI 56,780 and P4Q-158 were the most active, with low nanomolar activity in vitro and causal prophylactic activity in vivo. This potent activity makes these compounds ideal candidates for advancement as novel antimalarials.

  8. Survey of Tetracyclines, Sulfonamides, Sulfamethazine, and Quinolones in UHT Milk in China Market

    Institute of Scientific and Technical Information of China (English)

    HAN Rong-wei; ZHENG Nan; WANG Jia-qi; ZHEN Yun-peng; LI Song-li; YU Qun-li

    2013-01-01

    This study surveyed 180 samples of ultra high temperature (UHT) milk of four top Chinese dairy brands collected in the 25 cities in China in June 2011, and assessed their contamination with antibiotics, using the ELISA method. The percentages of tetracyclines, sulfonamides, sulfamethazine, and quinolones detected in the samples were 0, 16.7, 40.6, and 100%, respectively. The maximum concentrations of the tetracyclines, sulfonamides, sulfamethazine and quinolones in UHT milk samples were<1.5, 26.2, 22.6, and 58.8μg kg-1, respectively. None of the samples exceeded the maximum residue levels (MRLs) for these four veterinary drugs, according to the regulations set by China, the European Union (EU) and the Codex Alimentarius Commission (CAC).

  9. Plant antimicrobial peptides as potential anticancer agents.

    Science.gov (United States)

    Guzmán-Rodríguez, Jaquelina Julia; Ochoa-Zarzosa, Alejandra; López-Gómez, Rodolfo; López-Meza, Joel E

    2015-01-01

    Antimicrobial peptides (AMPs) are part of the innate immune defense mechanism of many organisms and are promising candidates to treat infections caused by pathogenic bacteria to animals and humans. AMPs also display anticancer activities because of their ability to inactivate a wide range of cancer cells. Cancer remains a cause of high morbidity and mortality worldwide. Therefore, the development of methods for its control is desirable. Attractive alternatives include plant AMP thionins, defensins, and cyclotides, which have anticancer activities. Here, we provide an overview of plant AMPs anticancer activities, with an emphasis on their mode of action, their selectivity, and their efficacy.

  10. Dynamics of quinolone resistance in fecal Escherichia coli of finishing pigs after ciprofloxacin administration.

    Science.gov (United States)

    Huang, Kang; Xu, Chang-Wen; Zeng, Bo; Xia, Qing-Qing; Zhang, An-Yun; Lei, Chang-Wei; Guan, Zhong-Bin; Cheng, Han; Wang, Hong-Ning

    2014-09-01

    Escherichia coli resistance to quinolones has now become a serious issue in large-scale pig farms of China. It is necessary to study the dynamics of quinolone resistance in fecal Escherichia coli of pigs after antimicrobial administration. Here, we present the hypothesis that the emergence of resistance in pigs requires drug accumulation for 7 days or more. To test this hypothesis, 26 pigs (90 days old, about 30 kg) not fed any antimicrobial after weaning were selected and divided into 2 equal groups: the experimental (EP) group and control (CP) group. Pigs in the EP group were orally treated daily with 5 mg ciprofloxacin/kg of body weight for 30 days, and pigs in the CP group were fed a normal diet. Fresh feces were collected at 16 time points from day 0 to day 61. At each time point, ten E. coli clones were tested for susceptibility to quinolones and mutations of gyrA and parC. The results showed that the minimal inhibitory concentration (MIC) for ciprofloxacin increased 16-fold compared with the initial MIC (0.5 µg/ml) after ciprofloxacin administration for 3 days and decreased 256-fold compared with the initial MIC (0.5 µg/ml) after ciprofloxacin withdrawal for 26 days. GyrA (S83L, D87N/ D87Y) and parC (S80I) substitutions were observed in all quinolone-resistant E. coli (QREC) clones with an MIC ≥8 µg/ml. This study provides scientific theoretical guidance for the rational use of antimicrobials and the control of bacterial resistance.

  11. "Changes in cartilage of rats after treatment with Quinolone and in Magnesium-deficient diet "

    Directory of Open Access Journals (Sweden)

    Shakibaei M

    2002-07-01

    Full Text Available Ultrastructural changes in immature articular carilage were studied after treatment of 5-weeks-old rats with ofloxacin, a fluoroquinolone, and in magnesium deficiency.We concluded that quinolone-induced arthropathy is probably due to chelation of functionally available magnesium in joint cartilage as magnesium deficiency in joint cartilage could impair chondrocyte-matrix- interaction which is mediated by cation-dependent integrin-receptors of the β1-subfamily. With immuno-histochemical methods using monoclonal and polyclonal antibodies we showed that B1 integrins were expressed in rat joint cartilage. Joint cartilage lesions were detected in ofloxacin-treated and magnesium-deficient rats. Lesions were more pronounced in the quinolone-treated group. Expression of several integrins was reduced in the vicinity of lesions after oral treatment with 2×600 mg ofloxacin/kg body wt for one day. Gross-structural lesions (e.g. cleft formation, unmasked collagen fibres in magnesium deficient rats were very similar but changes in intergrin expression were less pronounced. Alterations observed on the ultrastructural level showed striking similarities in magnesium-deficient rats and in rats treated with single doses of 600 mg ofloxacin per kg body wt.Typical observation were: bundle shaped, electron-dense aggregates on the surface and in the cytoplasm of chondrocytes, detachement of the cell membrance from the matrix and necrotic chondrocytes, reduced synthesis and/or reduced of extracellular matrix and swelling of cell organelles such as mitochondria.The results of this study confirm our previously reported finding that quinolone-induced arthropathy probably is caued by a reduction of functionally available magnesium (ionized Mg2+ in cartilage. Furthermore, they provide a basis for aimed studies with human cartilage samples from quinolone-treated patients which might be available postmortal or after hip replacement surgery

  12. (-)-Arctigenin as a lead compound for anticancer agent.

    Science.gov (United States)

    Chen, Gui-Rong; Li, Hong-Fu; Dou, De-Qiang; Xu, Yu-Bin; Jiang, Hong-Shuai; Li, Fu-Rui; Kang, Ting-Guo

    2013-01-01

    (-)-Arctigenin, an important active constituent of the traditional Chinese herb Fructus Arctii, was found to exhibit various bioactivities, so it can be used as a good lead compound for further structure modification in order to find a safer and more potent medicine. (-)-Arctigenin derivatives 1-5 of (-)-arctingen were obtained by modifying with ammonolysis at the lactone ring and sulphonylation at C (6') and C (6″) and O-demethylation at CH3O-C (3'), CH3O-C (3″) and CH3O-C (4″), and their anticancer bioactivities were examined.

  13. [Anticancer properties of Trichoderma asperellum 302 from buried soils].

    Science.gov (United States)

    Tukhbatova, R I; Fattakhova, A N; Alimova, F K

    2014-01-01

    Melanoma is one of the most malignant tumors, which leaves no chance of survival in the case of the "bang". There are various ways to treat tumors, however, recently in the field of cancer research, there are studies in which fungal metabolites have been used as antitumor agents. In this study we examined the effect of the culture fluid of the fungus Trichoderma asperellum 302 on the growth and development of melanoma B 16. We have shown that these culture fluid has anticancer properties, causing destruction of tumor tissue. Obtained data open new possibilities and prospects for the use of active substances derived from fungi in the complex therapy of cancer.

  14. Plasmid-mediated quinolone resistance in Enterobacteriaceae: a systematic review with a focus on Mediterranean countries.

    Science.gov (United States)

    Yanat, B; Rodríguez-Martínez, J-M; Touati, A

    2017-03-01

    Quinolones are a family of synthetic broad-spectrum antimicrobial drugs. These molecules have been widely prescribed to treat various infectious diseases and have been classified into several generations based on their spectrum of activity. Quinolones inhibit bacterial DNA synthesis by interfering with the action of DNA gyrase and topoisomerase IV. Mutations in the genes encoding these targets are the most common mechanisms of high-level fluoroquinolone resistance. Moreover, three mechanisms for plasmid-mediated quinolone resistance (PMQR) have been discovered since 1998 and include Qnr proteins, the aminoglycoside acetyltransferase AAC(6')-Ib-cr, and plasmid-mediated efflux pumps QepA and OqxAB. Plasmids with these mechanisms often encode additional antimicrobial resistance (extended spectrum beta-lactamases [ESBLs] and plasmidic AmpC [pAmpC] ß-lactamases) and can transfer multidrug resistance. The PMQR determinants are disseminated in Mediterranean countries with prevalence relatively high depending on the sources and the regions, highlighting the necessity of long-term surveillance for the future monitoring of trends in the occurrence of PMQR genes.

  15. Characterization of quinolone resistance in Salmonella spp. isolates from food products and human samples in Brazil.

    Science.gov (United States)

    Pribul, Bruno Rocha; Festivo, Marcia Lima; de Souza, Miliane Moreira Soares; Rodrigues, Dalia dos Prazeres

    2016-01-01

    Non-typhoidal salmonellosis is an important zoonotic disease caused by Salmonella enterica. The aim of this study was to investigate the prevalence of plasmid-mediated quinolone resistance in Salmonella spp. and its association with fluoroquinolone susceptibility in Brazil. A total of 129 NTS isolates (samples from human origin, food from animal origin, environmental, and animal) grouped as from animal (n=62) and human (n=67) food were evaluated between 2009 and 2013. These isolates were investigated through serotyping, antimicrobial susceptibility testing, and the presence of plasmid-mediated quinolone resistance (PMQR) genes (qnr, aac(6')-Ib) and associated integron genes (integrase, and conserved integron region). Resistance to quinolones and/or fluoroquinolones, from first to third generations, was observed. Fifteen isolates were positive for the presence of qnr genes (8 qnrS, 6 qnrB, and 1 qnrD) and twenty three of aac(6')-Ib. The conserved integron region was detected in 67 isolates as variable regions, from ±600 to >1000pb. The spread of NTS involving PMQR carriers is of serious concern and should be carefully monitored.

  16. A series of 2D metal-quinolone complexes: Syntheses, structures, and physical properties

    Science.gov (United States)

    He, Jiang-Hong; Xiao, Dong-Rong; Chen, Hai-Yan; Sun, Dian-Zhen; Yan, Shi-Wei; Wang, Xin; Ye, Zhong-Li; Luo, Qun-Li; Wang, En-Bo

    2013-02-01

    Six novel 2D metal-quinolone complexes, namely [Cd(cfH)(bpdc)]rad H2O (1), [M(norfH)(bpdc)]rad H2O (M=Cd (2) and Mn (3)), [Mn2(cfH)(odpa)(H2O)3]rad 0.5H2O (4), [Co2(norfH)(bpta)(μ2-H2O)(H2O)2]rad H2O (5) and [Co3(saraH)2(Hbpta)2(H2O)4]rad 9H2O (6) (cfH=ciprofloxacin, norfH=norfloxacin, saraH=sarafloxacin, bpdc=4,4'-biphenyldicarboxylate, odpa=4,4'-oxydiphthalate, bpta=3,3',4,4'-biphenyltetracarboxylate) have been synthesized and characterized. Compounds 1-3 consist of 2D arm-shaped layers based on the 1D {M(COO)}nn+ chains. Compounds 4 and 5 display 2D structures based on tetranuclear manganese or cobalt clusters with (3,6)-connected kgd topology. Compound 6 exhibits a 2D bilayer structure, which represents the first example of metal-quinolone complexes with 2D bilayer structure. By inspection of the structures of 1-6, it is believed that the long aromatic polycarboxylate ligands are important for the formation of 2D metal-quinolone complexes. The magnetic properties of compounds 3-6 was studied, indicating the existence of antiferromagnetic interactions. Furthermore, the luminescent properties of compounds 1-2 are discussed.

  17. 喹诺酮类药物的研究进展%Research Progress of Quinolones

    Institute of Scientific and Technical Information of China (English)

    田秋月

    2014-01-01

    喹诺酮类药物是一类人工合成的抗菌药物,目前广泛应用于临床抗感染治疗中,具有较强的抗菌活性。本文主要从喹诺酮类药物的作用机制、临床应用、不良反应及耐药机制等方面进行分析和整理,综述其研究进展并对其未来的研究方向提出了建议,希望为今后喹诺酮药物的研究提供一定的参考依据。%Quinolones are a group of synthetic antibacteril drugs with strong antibacterial activity which have a broad range of clinic applications in recent years. In this article, research progress of quinolones was analyzed and summarized from the aspects of action mechanism, clinical application, adverse reactions and drug resistance mechanism, and the future research direction of quinolones was proposed.

  18. Liquid chromatographic determination of quinolones in water and human urine samples after microextraction by packed sorbent.

    Science.gov (United States)

    Rani, Susheela; Kumar, Ashwini; Malik, Ashok Kumar; Singh, Baldev

    2012-01-01

    A method for the simultaneous determination of quinolones in water and urine samples by microextraction in a sorbent-packed syringe (MEPS) with LC is described. MEPS is a new miniaturized SPE technique that can be used with chromatographic instruments without any modifications. In MEPS, approximately 1 mg of the solid packing material is inserted into a syringe (100-250 microL) as a plug. Sample preparation takes place on the packed bed. The new method is promising, easy to use, economical, and rapid. The determination of quinolones in groundwater and urine was performed using MEPS as a sample preparation method with LC-UV determination. Four quinolone antibiotics--enrofloxacin, enoxacin, danofloxacin, and nalidixic acid--in groundwater and urine samples were used as analytes. The extraction recovery was found to be between 64.9 and 98.9%. The results showed high correlation coefficients (R2 > 0.992) for all of the analytes within the calibration range. The LOQ was between 0.091 and 0.315 ng/mL.

  19. Renaissance of antibiotics against difficult infections: Focus on oritavancin and new ketolides and quinolones.

    Science.gov (United States)

    Van Bambeke, Françoise

    2014-11-01

    Lipoglycopeptide, ketolide, and quinolone antibiotics are currently in clinical development, with specific advantages over available molecules within their respective classes. The lipoglycopeptide oritavancin is bactericidal against MRSA, vancomycin-resistant enterococci, and multiresistant Streptococcus pneumoniae, and proved effective and safe for the treatment of acute bacterial skin and skin structure infection (ABSSSI) upon administration of a single 1200 mg dose (two completed phase III trials). The ketolide solithromycin (two phase III studies recruiting for community-acquired pneumonia) shows a profile of activity similar to that of telithromycin, but in vitro data suggest a lower risk of hepatotoxicity, visual disturbance, and aggravation of myasthenia gravis due to reduced affinity for nicotinic receptors. Among quinolones, finafloxacin and delafloxacin share the unique property of an improved activity in acidic environments (found in many infection sites). Finafloxacin (phase II completed; activity profile similar to that of ciprofloxacin) is evaluated for complicated urinary tract and Helicobacter pylori infections. The other quinolones (directed towards Gram-positive pathogens) show improved activity on MRSA and multiresistant S. pneumoniae compared to current molecules. They are in clinical evaluation for ABSSSI (avarofloxacin (phase II completed), nemonoxacin and delafloxacin (ongoing phase III)), respiratory tract infections (zabofloxacin and nemonoxacin (ongoing phase III)), or gonorrhea (delafloxacin).

  20. Characterization of quinolone resistance in Salmonella spp. isolates from food products and human samples in Brazil

    Science.gov (United States)

    Pribul, Bruno Rocha; Festivo, Marcia Lima; de Souza, Miliane Moreira Soares; dos Prazeres Rodrigues, Dalia

    2016-01-01

    Non-typhoidal salmonellosis is an important zoonotic disease caused by Salmonella enterica. The aim of this study was to investigate the prevalence of plasmid-mediated quinolone resistance in Salmonella spp. and its association with fluoroquinolone susceptibility in Brazil. A total of 129 NTS isolates (samples from human origin, food from animal origin, environmental, and animal) grouped as from animal (n = 62) and human (n = 67) food were evaluated between 2009 and 2013. These isolates were investigated through serotyping, antimicrobial susceptibility testing, and the presence of plasmid-mediated quinolone resistance (PMQR) genes (qnr, aac(6′)-Ib) and associated integron genes (integrase, and conserved integron region). Resistance to quinolones and/or fluoroquinolones, from first to third generations, was observed. Fifteen isolates were positive for the presence of qnr genes (8 qnrS, 6 qnrB, and 1 qnrD) and twenty three of aac(6′)-Ib. The conserved integron region was detected in 67 isolates as variable regions, from ±600 to >1000 pb. The spread of NTS involving PMQR carriers is of serious concern and should be carefully monitored. PMID:26887245

  1. SOME IMPORTANT ANTICANCER HERBS: A REVIEW

    Directory of Open Access Journals (Sweden)

    Pandey Govind

    2011-07-01

    Full Text Available A great deal of pharmaceutical research has considerably improved the quality of herbal drugs used against various types of cancer. With the advanced knowledge of molecular science and the refinement in isolation and structure elucidation techniques, we are in a much better position now to identify various anticancer herbs. Scientists all over the world are concentrating on the use of herbs to boost immune system of the body against cancer. Scientists have contributed for a number of years to identify hundreds of anticancer herbs, and developed various herbal formulations from their active principles that inhibit growth and spread of cancer without any side effect. Such herbs possess anticancer, immunoenhancing, antiangiogenesis, antioxidant and antimutagenic properties. They inhibit growth and spread of cancer by modulating the activity of hormones, enzymes and other biological factors. The therapeutic effect of these herbs is executed by the complex synergistic interaction among their various active principles. Some important anticancer herbs have been discussed here.

  2. Anticancer Properties of Capsaicin Against Human Cancer.

    Science.gov (United States)

    Clark, Ruth; Lee, Seong-Ho

    2016-03-01

    There is persuasive epidemiological and experimental evidence that dietary phytochemicals have anticancer activity. Capsaicin is a bioactive phytochemical abundant in red and chili peppers. While the preponderance of the data strongly indicates significant anticancer benefits of capsaicin, more information to highlight molecular mechanisms of its action is required to improve our knowledge to be able to propose a potential therapeutic strategy for use of capsaicin against cancer. Capsaicin has been shown to alter the expression of several genes involved in cancer cell survival, growth arrest, angiogenesis and metastasis. Recently, many research groups, including ours, found that capsaicin targets multiple signaling pathways, oncogenes and tumor-suppressor genes in various types of cancer models. In this review article, we highlight multiple molecular targets responsible for the anticancer mechanism of capsaicin. In addition, we deal with the benefits of combinational use of capsaicin with other dietary or chemotherapeutic compounds, focusing on synergistic anticancer activities.

  3. Targeted anticancer therapy: overexpressed receptors and nanotechnology.

    Science.gov (United States)

    Akhtar, Mohd Javed; Ahamed, Maqusood; Alhadlaq, Hisham A; Alrokayan, Salman A; Kumar, Sudhir

    2014-09-25

    Targeted delivery of anticancer drugs to cancer cells and tissues is a promising field due to its potential to spare unaffected cells and tissues, but it has been a major challenge to achieve success in these therapeutic approaches. Several innovative approaches to targeted drug delivery have been devised based on available knowledge in cancer biology and on technological advancements. To achieve the desired selectivity of drug delivery, nanotechnology has enabled researchers to design nanoparticles (NPs) to incorporate anticancer drugs and act as nanocarriers. Recently, many receptor molecules known to be overexpressed in cancer have been explored as docking sites for the targeting of anticancer drugs. In principle, anticancer drugs can be concentrated specifically in cancer cells and tissues by conjugating drug-containing nanocarriers with ligands against these receptors. Several mechanisms can be employed to induce triggered drug release in response to either endogenous trigger or exogenous trigger so that the anticancer drug is only released upon reaching and preferentially accumulating in the tumor tissue. This review focuses on overexpressed receptors exploited in targeting drugs to cancerous tissues and the tumor microenvironment. We briefly evaluate the structure and function of these receptor molecules, emphasizing the elegant mechanisms by which certain characteristics of cancer can be exploited in cancer treatment. After this discussion of receptors, we review their respective ligands and then the anticancer drugs delivered by nanotechnology in preclinical models of cancer. Ligand-functionalized nanocarriers have delivered significantly higher amounts of anticancer drugs in many in vitro and in vivo models of cancer compared to cancer models lacking such receptors or drug carrying nanocarriers devoid of ligand. This increased concentration of anticancer drug in the tumor site enabled by nanotechnology could have a major impact on the efficiency of cancer

  4. Modulation of anticancer drug toxicity by solcoseryl.

    Science.gov (United States)

    Sołtysiak-Pawluczuk, D; Jedrych, A; Jastrzebski, Z; Czyzewska-Szafran, H; Danysz, A

    1991-01-01

    The studies of the effect of solcoseryl on toxicity of selected anticancer drugs were performed in mice. The observed differential influence of solcoseryl was dependent on the type of anticancer drug as well as on the schedule of solcoseryl administration. The protective effect of the biostimulator was noticed exclusively against 5-FU toxicity. The results of our studies could provide possible implications for therapeutic approach.

  5. Detection of quinolones in commercial eggs obtained from farms in the Espaíllat Province in the Dominican Republic.

    Science.gov (United States)

    Moscoso, S; de los Santos, F Solís; Andino, A G; Diaz-Sanchez, Sandra; Hanning, I

    2015-01-01

    Previously, we reported the use of quinolones in broiler chickens resulted in residues in retail poultry meat obtained from nine districts in the Santiago Province of the Dominican Republic. Residues in poultry products are a concern due to consumer allergies and the potential to develop antibiotic-resistant bacteria. Given the use of quinolones in poultry production and our previous findings in poultry meat, the objective of this study was to evaluate the presence of quinolone residues in eggs. Samples were collected from 48 different farms located in three of the four municipalities (Moca, Cayetano Germosén, and Jamao) of the Espaíllat Province. Each farm was sampled three times between July and September for a total of 144 samples. Samples were evaluated qualitatively and quantitatively for quinolone residues using the Equinox test. Operation systems (cage or floor), seasonality, and location were considered along with egg-producer sizes that were defined as small scale, 60,000 eggs per day. From small-, medium-, and large-scale producers, 69, 50, and 40% of samples were positive for quinolone residues, respectively. A greater number of samples were positive (61%) in floor-laying hen producers compared with those using cages (40%). In the Jamao municipality, 67% of the samples were positive compared with Moca and Cayetano Germosén, where 56 and 25% of samples were positive, respectively. Sampling time had an effect on percent positives: samples collected in July, August, and September were 71, 19, and 63% positive, respectively. Overall, 51% of the samples obtained from eggs produced in the province of Espaíllat were positive for quinolone residues at levels higher than the maximum limits for edible tissue established by the regulatory agencies, including the European Union and U.S. Department of Agriculture. The results obtained from this research confirmed the presence of quinolone residue in eggs, which may present a health risk to some consumers.

  6. Oncolytic viruses as anticancer vaccines

    Directory of Open Access Journals (Sweden)

    Norman eWoller

    2014-07-01

    Full Text Available Oncolytic virotherapy has shown impressive results in preclinical studies and first promising therapeutic outcomes in clinical trials as well. Since viruses are known for a long time as excellent vaccination agents, oncolytic viruses are now designed as novel anticancer agents combining the aspect of lysis-dependent cytoreductive activity with concomitant induction of antitumoral immune responses. Antitumoral immune activation by oncolytic virus infection of tumor tissue comprises both, immediate effects of innate immunity and also adaptive responses for long lasting antitumoral activity which is regarded as the most prominent challenge in clinical oncology. To date, the complex effects of a viral tumor infection on the tumor microenvironment and the consequences for the tumor-infiltrating immune cell compartment are poorly understood. However, there is more and more evidence that a tumor infection by an oncolytic virus opens up a number of options for further immunomodulating interventions such as systemic chemotherapy, generic immunostimulating strategies, dendritic cell-based vaccines, and antigenic libraries to further support clinical efficacy of oncolytic virotherapy.

  7. Characteristics of Quinolone Resistance in Salmonella spp. Isolates from the Food Chain in Brazil.

    Science.gov (United States)

    Pribul, Bruno R; Festivo, Marcia L; Rodrigues, Marcelle S; Costa, Renata G; Rodrigues, Elizabeth C Dos P; de Souza, Miliane M S; Rodrigues, Dalia Dos P

    2017-01-01

    Salmonella spp. is an important zoonotic pathogen related to foodborne diseases. Despite that quinolones/fluoroquinolones are considered a relevant therapeutic strategy against resistant isolates, the increase in antimicrobial resistance is an additional difficulty in controlling bacterial infections caused by Salmonella spp. Thus, the acquisition of resistance to quinolones in Salmonella spp. is worrisome to the scientific community along with the possibility of transmission of resistance through plasmids. This study investigated the prevalence of plasmid-mediated quinolone resistance (PMQR) in Salmonella spp. and its association with fluoroquinolone susceptibility in Brazil. We evaluated 129 isolates, 39 originated from food of animal sources, and 14 from environmental samples and including 9 from animals and 67 from humans, which were referred to the National Reference Laboratory of Enteric Diseases (NRLEB/IOC/RJ) between 2009 and 2013. These samples showed a profile of resistance for the tested quinolones/fluoroquinolones. A total of 33 serotypes were identified; S. Typhimurium (63) was the most prevalent followed by S. Enteritidis (25). The disk diffusion test showed 48.8% resistance to enrofloxacin, 42.6% to ciprofloxacin, 39.53% to ofloxacin, and 30.2% to levofloxacin. According to the broth microdilution test, the resistance percentages were: 96.1% to nalidixic acid, 64.3% to enrofloxacin, 56.6% to ciprofloxacin, 34.1% to ofloxacin, and 30.2% to levofloxacin. Qnr genes were found in 15 isolates (8 qnrS, 6 qnrB, and 1 qnrD), and the aac(6')-Ib gene in 23. The integron gene was detected in 67 isolates with the variable region between ±600 and 1000 bp. The increased detection of PMQR in Salmonella spp. is a serious problem in Public Health and must constantly be monitored. Pulsed-field gel electrophoresis was performed to evaluated clonal profile among the most prevalent serovars resistant to different classes of quinolones. A total of 33 pulsotypes of S

  8. Antiparasitic and anticancer carvotacetone derivatives of Sphaeranthus bullatus

    Science.gov (United States)

    The CH2Cl2-MeOH (1:1) extract of the aerial parts of Sphaeranthus bullatus, an annual herb native to tropical East Africa, showed activity against chloroquine sensitive D6 (IC50 9.7 µg/ml) and chloroquine resistant W2 (IC50 15.0 µg/ml) strains of P. falciparum. Seventeen secondary metabolites were i...

  9. Looking for the new preparations for antibacterial therapy III. New antimicrobial agents from the quinolones group in clinical trials.

    Science.gov (United States)

    Karpiuk, Izabela; Tyski, Stefan

    2013-01-01

    There is an essential need for searching for the new compounds effective in the treatment of infections caused by multidrug-resistant bacteria. This paper is the third part of a series associated with the exploration of new antibacterial agents and it discusses the compounds belonging to the group of quinolones and substances possessing a hybrid structure composed of the quinolone molecule and other compounds. Eleven new substances at the stage of clinical trials are presented. Three of them belong to the group of non-fluorinated quinolone (nemonoxacin, ozenoxacin and KRP-AM 1977X), while six are the quinolones containing fluorine atom at 6 position of the carbon atom in the quinoline ring (zabofloxacin, finafloxacin, delafloxacin, JNJ-Q2, WCK771 and KPI-10). The remaining two compounds possess a hybrid construction composed of the quinolone structure and other molecules (cadazolid and CBR-2092). There is a chance in the near future, that the presented compounds can extend the range of existing antibacterial drugs and provide an alternative to currently available medicinal products.

  10. High-level quinolone resistance is associated with the overexpression of smeVWX in Stenotrophomonas maltophilia clinical isolates.

    Science.gov (United States)

    García-León, G; Ruiz de Alegría Puig, C; García de la Fuente, C; Martínez-Martínez, L; Martínez, J L; Sánchez, M B

    2015-05-01

    Stenotrophomonas maltophilia is the only known bacterium in which quinolone-resistant isolates do not present mutations in the genes encoding bacterial topoisomerases. The expression of the intrinsic quinolone resistance elements smeDEF, smeVWX and Smqnr was analysed in 31 clinical S. maltophilia isolates presenting a minimum inhibitory concentration (MIC) range to ciprofloxacin between 0.5 and > 32 μg/mL; 11 (35.5%) overexpressed smeDEF, 2 (6.5%) presenting the highest quinolone MICs overexpressed smeVWX and 1 (3.2%) overexpressed Smqnr. Both strains overexpressing smeVWX presented changes at the Gly266 position of SmeRv, the repressor of smeVWX. Changes at the same position were previously observed in in vitro selected S. maltophilia quinolone-resistant mutants, indicating this amino acid is highly relevant for the activity of SmeRv in repressing smeVWX expression. For the first time SmeVWX overexpression is associated with quinolone resistance of S. maltophilia clinical isolates.

  11. Quinoxaline Nucleus: A Promising Scaffold in Anti-cancer Drug Discovery.

    Science.gov (United States)

    Pinheiro, Alessandra C; Mendonça Nogueira, Thais C; de Souza, Marcus V N

    2016-01-01

    Heterocyclic compounds are a class of substances, which play a critical role in modern drug discovery being incorporated in the structure of a large variety of drugs used in many different types of diseases. Quinoxaline is an important heterocyclic nucleus with a wide spectrum of biological activities, and recently much attention has been found on anticancer drug discovery based on this class. Owing to the importance of this system, the aim of this review is to provide an update on the synthesis and anticancer activity of quinoxaline derivatives covering articles published between 2010 and 2015.

  12. Mild and efficient Winterfeldt oxidation of 1,2,3,4-tetrahydro-γ-carbolines for the synthesis of dihydropyrrolo[3,2-b]-quinolones and pyrrolo[3,2-b]quinolones.

    Science.gov (United States)

    Sheng, Rong; Zhu, Jiangwei; Hu, Yongzhou

    2012-01-30

    The Winterfeldt oxidation (NaOH, DMF, air, rt) of substituted 1,2,3,4-tetrahydro-γ-carbolines has been developed, which provides a convenient and efficient method for the synthesis of the corresponding dihydropyrrolo[3,2-b]quinolones in moderate to excellent yields (38-94%). The generality and substrate scope of this reaction are explored and a possible mechanism is proposed. The results imply that electron-withdrawing groups on N2 of tetrahydro-γ-carbolines and N5-H are necessary. The synthesis of 5 or 7-substituted pyrrolo[3,2-b]quinolones in near quantitative yields was also achieved through deprotection and aromatization of N1-Boc-dihydropyrrolo[3,2-b]quinolones.

  13. Quinoxaline-Based Scaffolds Targeting Tyrosine Kinases and Their Potential Anticancer Activity.

    Science.gov (United States)

    El Newahie, Aliya M S; Ismail, Nasser S M; Abou El Ella, Dalal A; Abouzid, Khaled A M

    2016-05-01

    Quinoxaline derivatives, also called benzopyrazines, are an important class of heterocyclic compounds. Quinoxalines have drawn great attention due to their wide spectrum of biological activities. They are considered as an important basis for anticancer drugs due to their potential activity as protein kinase inhibitors. In this review, we focus on the chemistry of the quinoxaline derivatives, the strategies for their synthesis, their potential activities against various tyrosine kinases, and on the structure-activity relationship studies reported to date.

  14. Discovery of a new function of curcumin which enhances its anticancer therapeutic potency.

    Science.gov (United States)

    Nagahama, Koji; Utsumi, Tomoya; Kumano, Takayuki; Maekawa, Saeko; Oyama, Naho; Kawakami, Junji

    2016-08-01

    Curcumin has received immense attention over the past decades because of its diverse biological activities and recognized as a promising drug candidate in a large number of diseases. However, its clinical application has been hindered due to extremely low aqueous solubility, chemical stability, and cellular uptake. In this study, we discovered quite a new function of curcumin, i.e. pH-responsive endosomal disrupting activity, derived from curcumin's self-assembly. We selected anticancer activity as an example of biological activities of curcumin, and investigated the contribution of pH-responsive property to its anticancer activity. As a result, we demonstrated that the pH-responsive property significantly enhances the anticancer activity of curcumin. Furthermore, we demonstrated a utility of the pH-responsive property of curcumin as delivery nanocarriers for doxorubicin toward combination cancer therapy. These results clearly indicate that the smart curcumin assemblies act as promising nanoplatform for development of curcumin-based therapeutics.

  15. Discovery of a new function of curcumin which enhances its anticancer therapeutic potency

    Science.gov (United States)

    Nagahama, Koji; Utsumi, Tomoya; Kumano, Takayuki; Maekawa, Saeko; Oyama, Naho; Kawakami, Junji

    2016-08-01

    Curcumin has received immense attention over the past decades because of its diverse biological activities and recognized as a promising drug candidate in a large number of diseases. However, its clinical application has been hindered due to extremely low aqueous solubility, chemical stability, and cellular uptake. In this study, we discovered quite a new function of curcumin, i.e. pH-responsive endosomal disrupting activity, derived from curcumin’s self-assembly. We selected anticancer activity as an example of biological activities of curcumin, and investigated the contribution of pH-responsive property to its anticancer activity. As a result, we demonstrated that the pH-responsive property significantly enhances the anticancer activity of curcumin. Furthermore, we demonstrated a utility of the pH-responsive property of curcumin as delivery nanocarriers for doxorubicin toward combination cancer therapy. These results clearly indicate that the smart curcumin assemblies act as promising nanoplatform for development of curcumin-based therapeutics.

  16. The anticancer properties of Salvia miltiorrhiza Bunge (Danshen): a systematic review.

    Science.gov (United States)

    Chen, Xiuping; Guo, Jiajie; Bao, Jiaolin; Lu, Jinjian; Wang, Yitao

    2014-07-01

    Salvia miltiorrhiza Bunge (Danshen in Chinese) is a classical Huoxue Huayu (a traditional Chinese medical term means promoting blood circulation and removing blood stasis) herb with 1000 years of clinical application. It mainly contains two groups of ingredients: the hydrophilic phenolic acids and the lipophilic tanshinones. Both groups have demonstrated multiple bioactivities, such as antioxidative stress, antiplatelet aggregation, anti-inflammation, among others. Recent data have demonstrated that its lipophilic compounds, especially the tanshinones, show potent anticancer activities both in vitro and in vivo. The anticancer effects of the hydrophilic phenolic acids have also been reported. Furthermore, tanshinones provide structural skeletons for chemical modifications, allowing for a series of derivatives of interests. This review provides a systematic summary of the anticancer profile and the underlying mechanisms of the bioactive compounds isolated from Danshen with special emphasis on tanshinones, aiming to bring new insights for further research and development of this ancient herb.

  17. The molecular physiological and genetic mechanisms underlying the superb efficacy of quinolones%喹诺酮类药物作用的生理和遗传的分子机制

    Institute of Scientific and Technical Information of China (English)

    龙泉鑫; 何颖; 谢建平

    2012-01-01

    氟喹诺酮类药物是目前使用最广泛的广谱抗生素,占据了全球抗生素类药物市场约18%的份额.其杀菌快速,而且具备大量的衍生物库,为药物更新换代提供了良好的基础.但这些衍生物在杀菌的速度、代谢过程中对氧需求、对蛋白合成的依赖性等方面的差异很大.从药物作用后细菌分子遗传层面的应答特征揭示各类衍生物的深层次作用机制,可以为寻找更有效的新喹诺酮类药物提供坚实基础.SOS应答、毒素-抗毒素系统,细菌程序性死亡、染色体片段化以及活性氧簇等新机制可能不同程度参与了喹诺酮类药物的杀菌过程.本文重点介绍喹诺酮作用的“二步特征”.该特征的引入有助于理解不同喹诺酮类药物的杀菌特征,也有助于开发新的喹诺酮类药物.%The fluoroquinolones are the most widely used broad-spectrum antibiotics, accounting for 18% of global antibacterial market share. They can kill bacteria rapidly with variety of derivatives available. Different quinolones vary significantly in rate and spectrum of killing, oxygen requirement for metabolism and reliance upon protein synthesis. Further understanding the sophisticated mechanisms of action of this important antibiotic family based on the molecular genetic response of bacteria can facilitate the discovery of better quinolone derivatives. Factors such as SOS response, bacterial toxin-antitoxin system, programmed death, chromosome fragmentation and reactive oxygen have been implicated in the action to some extent. "Two steps characteristic" of quinolones killing is also emphasized, which might inspire future better quinolones modification.

  18. Recent Developments on 1,2,4-Triazole Nucleus in Anticancer Compounds: A Review.

    Science.gov (United States)

    Kaur, Ramandeep; Dwivedi, Ashish Ranjan; Kumar, Bhupinder; Kumar, Vinod

    2016-01-01

    1,2,4-triazole is an important nucleus present in a large number of compounds. More than thirty-five compounds containing this nucleus are introduced into the market. 1,2,4-triazole nucleus is stable to metabolism and acts as an important pharmacophore by interacting at the active site of a receptor as hydrogen bond acceptor and as a donor. Due to its polar nature, the triazole nucleus can increase the solubility of the ligand and it can significantly improve the pharmacological profile of the drug. A large number of 1,2,4-triazole derivatives are reported to possess a wide range of bioactivities including anti-cancer activity. This review article describes the role of 1,2,4-triazole nucleus in different types of anti-cancer agents such as nucleoside based anti-cancer agents, kinase inhibitors, tubulin modulators, aromatase and steroid sulfatase inhibitors, methionine aminopeptidase inhibitors, tankyrase inhibitors and metal complex based anti-cancer agents. It is expected that the current review article will provide insight into various ligand-receptor interactions and help in the rational design and development of novel 1,2,4-triazole based anti-cancer drugs with improved selectivity for cancer cells.

  19. USE OF QUINOLONES IN BULL SEMEN EXTENDERS TO REDUCE SPERM DEOXYRIBONUCLEIC ACID DAMAGE

    Directory of Open Access Journals (Sweden)

    Clara Gonzalez-Marin

    2012-01-01

    Full Text Available Cryopreserved sperm samples from Holstein bulls (n = 20 were examined for bacterial presence and Sperm DNA Fragmentation (SDF dynamics. SDF was assessed after thawing (T0 and at 4, 24 and 48 h of incubation (37°C and the rate of SDF (r-SDF, as an estimator of the DNA degradation over time, was calculated. Two groups of bulls were identified based on the presence or absence of bacteria: One group (n = 10 had a readily detectable bacterial presence, while the other group (n = 10 had an undetectable bacterial presence. Differences in the SDF at T0 were not observed between these two groups. However, statistically different results were found after 24 h of incubation at 37°C (Kaplan-Meier estimator; Log-Rank Matel-Cox, p-1 of ciprofloxacin at T0. Differences in the r-SDF (p>0.05 were not detected between the control and the quinolone treated sample for those samples without bacteria. However, differences (p<0.000 in SDF were observed for quinolone treated samples that previously presented bacteria. Incubation of sealed straws showed that bacterial contamination occurred prior to cryopreservation. These results call attention to three points: (1 sperm samples were in contact with bacteria before cryopreservation; (2 the r-SDF can be directly correlated with bacterial presence but this effect remains cryptic after thawing and (3 the r-SDF can be reduced by treating the semen samples with an adequate antibiotic such as quinolones, a finding not previously reported in the scientific literature, but important in terms of reproduction.

  20. Characterization of quinolone resistance mechanisms in Enterobacteriaceae recovered from diseased companion animals in Europe.

    Science.gov (United States)

    Guillard, T; de Jong, A; Limelette, A; Lebreil, A L; Madoux, J; de Champs, C

    2016-10-15

    ComPath is a European monitoring programme dedicated to the collection of bacterial pathogens from diseased dogs and cats to determine their antibiotic susceptibility. The objective was to characterize genetic determinants associated with quinolone resistance among 69 enrofloxacin non-wild type strains selected among 604 non-duplicate Enterobacteriaceae isolates collected in 10EU countries from 2008 to 2010: quinolone resistance determining region (QRDR) and plasmid-mediated quinolone resistance (PMQR). Among them, 17% (12/69) carried at least one PMQR (9/12 qnrB, qnrS or qnrD and 4/12 aac(6')-Ib-cr) and 83% (57/69) no PMQR. All the Klebsiella pneumoniae isolates chromosomally carried oqxAB . No qepA genes were detected. Eight strains did not carry any mutations in QRDR (4 PMQR-positive and 4 PMQR-negative strains). From the 12 PMQR-positive strains, 4 showed enrofloxacin MICs≤2μg/mL, and 8 MICs≥8μg/mL (resistant). These latter strains carried 1-5 mutations in QRDR, including a ParE I529L mutation. qnrD was found in 2 Proteus mirabilis and the plasmids were similar to pDIJ09-518a previously described. For the 57 non-PMQR strains, 29 strains showed MICs≤2μg/mL (4 with no QRDR mutations, 21 with 1 mutation in GyrA, 4 with 2 mutations in GyrA) and 28 showed enrofloxacin MICs≥8μg/mL carrying at least 2 mutations in QRDR, including a ParE I529L mutation for 2 Escherichia coli strains with a total of 5 QRDR mutations. No GyrB mutations were found. qnr was the major PMQR and qnrD was only detected in Proteus spp. Twelve strains carried at least 4 mutations.

  1. Genetic analysis of a pediatric clinical isolate of Moraxella catarrhalis with resistance to macrolides and quinolones.

    Science.gov (United States)

    Iwata, Satoshi; Sato, Yoshitake; Toyonaga, Yoshikiyo; Hanaki, Hideaki; Sunakawa, Keisuke

    2015-04-01

    During the surveillance conducted in 2012 by the Drug-resistant Pathogen Surveillance Group in Pediatric Infectious Disease, we isolated a strain of Moraxella catarrhalis that demonstrated resistance to both macrolides and quinolones from a male pediatric patient aged 1.5 years who had developed acute bronchitis. Then we evaluated the susceptibility of this strain to different types of antibacterial agents and conducted a genetic analysis. The results of the susceptibility evaluation showed that the MIC values of azithromycin, clarithromycin, and rokitamycin were >64 μg/mL, >64 μg/mL, and 4 μg/mL, respectively; clearly demonstrating resistance to macrolides. The MIC values of the quinolones levofloxacin, tosufloxacin, and garenoxacin were 4 μg/mL, 2 μg/mL, and 1 μg/mL, respectively; indicating decreased susceptibility. The genetic analysis of this strain revealed one mutation in 23s rRNA with a replacement of adenine by thymine at nucleotide position 2330 (A2330T) and another mutation in gyrB at nucleotide position 1481 by replacement of adenine with guanine (A1481G) that caused a substitution of the 494 th asparagine acid by glycine, as being associated with the observed resistance to macrolides and quinolones, respectively. Similar to drug-resistant bacteria Streptococcus pneumoniae and Haemophilus influenzae, the prevalence of which has recently increased, the treatment of drug-resistant M. catarrhalis infections is considered difficult due to the development of resistance to different types of antibacterial agents. It is vital to maintain an unwavering focus on the trend toward an increasing number of drug-resistant M. catarrhalis strains and ensure the proper use of each antibacterial agent.

  2. Molecular epidemiological survey on quinolone resistance genotype and phenotype of Escherichia coli in septicemic broilers in Hebei, China.

    Science.gov (United States)

    Xie, Rong; Huo, Shuying; Li, Yurong; Chen, Ligong; Zhang, Feiyan; Wu, Xianjun

    2014-02-01

    In this study, the quinolone-resistant determining region (QRDR) of gyrA of Escherichia coli and plasmid-mediated quinolone resistance (PMQR) genes, qnr(qnrA, qnrB, and qnrS), and aac(6 ')-Ib-cr were detected, sequenced, and analyzed. In addition, antimicrobial susceptibility tests (using the Kirby-Bauer disc diffusion method) were performed for all 111 E. coli isolates from septicemic broilers in Hebei, China. The results show that the resistance rates were as follows: ofloxacin 99.10%, ciprofloxacin 93.69%, levofloxacin 91.89%, norfloxacin 90.09%, and gatifloxacin 76.58%. Of the PMQR genes examined, aac(6 ')-Ib-cr (36.04%) was the most frequently identified gene in all isolates, followed by qnrS (8.11%), qnrB (0.90%), and qnrA (0%). Of the QRDR examined in the 40 phenotypic quinolone-resistant isolates, compared with the gyrA(+) gene of E. coli K-12, 4 amino acid exchanges were found, namely Ser-83→Asp, Asp-87→Asn, Asp-87→Tyr, and Asp-87→Ala, and all 40 isolates had 1 or 2 exchanges in QRDR. It was concluded that quinolone-resistance in E. coli remains a serious problem in Hebei, China. Therefore, there is considerable local surveillance of quinolone resistance. Plasmid-mediated quinolone resistance of the qnr type remains rare in Hebei, China, and mutation in QRDR may be the main problem.

  3. Anticancer activity of Carica papaya: a review.

    Science.gov (United States)

    Nguyen, Thao T T; Shaw, Paul N; Parat, Marie-Odile; Hewavitharana, Amitha K

    2013-01-01

    Carica papaya is widely cultivated in tropical and subtropical countries and is used as food as well as traditional medicine to treat a range of diseases. Increasing anecdotal reports of its effects in cancer treatment and prevention, with many successful cases, have warranted that these pharmacological properties be scientifically validated. A bibliographic search was conducted using the key words "papaya", "anticancer", and "antitumor" along with cross-referencing. No clinical or animal cancer studies were identified and only seven in vitro cell-culture-based studies were reported; these indicate that C. papaya extracts may alter the growth of several types of cancer cell lines. However, many studies focused on specific compounds in papaya and reported bioactivity including anticancer effects. This review summarizes the results of extract-based or specific compound-based investigations and emphasizes the aspects that warrant future research to explore the bioactives in C. papaya for their anticancer activities.

  4. Anticancer Properties of Phyllanthus emblica (Indian Gooseberry).

    Science.gov (United States)

    Zhao, Tiejun; Sun, Qiang; Marques, Maud; Witcher, Michael

    2015-01-01

    There is a wealth of information emanating from both in vitro and in vivo studies indicating fruit extract of the Phyllanthus emblica tree, commonly referred to as Indian Gooseberries, has potent anticancer properties. The bioactivity in this extract is thought to be principally mediated by polyphenols, especially tannins and flavonoids. It remains unclear how polyphenols from Phyllanthus emblica can incorporate both cancer-preventative and antitumor properties. The antioxidant function of Phyllanthus emblica can account for some of the anticancer activity, but clearly other mechanisms are equally important. Herein, we provide a brief overview of the evidence supporting anticancer activity of Indian Gooseberry extracts, suggest possible mechanisms for these actions, and provide future directions that might be taken to translate these findings clinically.

  5. Anticancer Properties of Phyllanthus emblica (Indian Gooseberry

    Directory of Open Access Journals (Sweden)

    Tiejun Zhao

    2015-01-01

    Full Text Available There is a wealth of information emanating from both in vitro and in vivo studies indicating fruit extract of the Phyllanthus emblica tree, commonly referred to as Indian Gooseberries, has potent anticancer properties. The bioactivity in this extract is thought to be principally mediated by polyphenols, especially tannins and flavonoids. It remains unclear how polyphenols from Phyllanthus emblica can incorporate both cancer-preventative and antitumor properties. The antioxidant function of Phyllanthus emblica can account for some of the anticancer activity, but clearly other mechanisms are equally important. Herein, we provide a brief overview of the evidence supporting anticancer activity of Indian Gooseberry extracts, suggest possible mechanisms for these actions, and provide future directions that might be taken to translate these findings clinically.

  6. [Residues of tetracycline and quinolones in wild fish living around a salmon aquaculture center in Chile].

    Science.gov (United States)

    Fortt Z, Antonia; Cabello C, Felipe; Buschmann R, Alejandro

    2007-02-01

    The presence of residues of tetracycline, quinolones and antiparasitic drugs was investigated in wild fish captured around salmon aquaculture pens in Cochamó, Region X, Chile. Residues of both antibiotics were found in the meta [corrected] of two species of wild fish that are consumed by humans, robalo (Elginops maclovinus) and cabrilla (Sebastes capensis) [corrected] These findings suggest that the antibiotic usage in salmon aquaculture in Chile has nvironmental implications that may affect human and animal health. More studies are needed in Chile to determine the relevance of these findings for human and animal health and the environment to regulate this use of antibiotics.

  7. Comparison of Antimicrobial Properties of Nano Quinolone with its Microscale Effects

    Science.gov (United States)

    Behbahani, G. Rezaie; Sadr, M. Hossaini; Nabipour, H.; Behbahani, H. Rezaei; Vahedpour, M.; Barzegar, L.

    2013-06-01

    Nano nalidixic acid was prepared by ultrasonic method in carbon tetrachloride. Nano nalidixic acid (quinolone antibiotic) was characterized by X-ray diffraction (XRD), infrared spectroscopy (IR) and scanning electron microscope (SEM). The antibacterial activities of nano nalidixic acid were tested against microorganisms and compared with the microscale drug. The results show that nano nalidixic acid has good inhibitory properties against two Gram-positive species, Staphylococcus aureus and Bacillus subtilis. Nano nalidixic acid also showed good antifungal activity against Candida albicans. Nano nalidixic acid can be injected into the human body as a decontaminating agent to prevent the growth of harmful microorganisms more effectively than the micro-sized drug.

  8. Functions of a GyrBA fusion protein and its interaction with QnrB and quinolones.

    Science.gov (United States)

    Chen, Chunhui; Villet, Regis; Jacoby, George A; Hooper, David C

    2015-11-01

    In order to study the interactions between Escherichia coli DNA gyrase and the gyrase interacting protein QnrB in vivo, we constructed a gyrB-gyrA fusion and validated its ability to correct the temperature-sensitive growth of gyrA and gyrB mutants. Like wild-type gyrA, the gyrB-gyrA fusion complemented a quinolone-resistant gyrA mutant to increase susceptibility. It functioned as an active type II topoisomerase, catalyzed negative supercoiling of DNA, was inhibited by quinolone, and was protected by QnrB.

  9. Studies with Myrtus communis L.: Anticancer properties.

    Science.gov (United States)

    Ogur, Recai

    2014-01-01

    Myrtus communis (MC) L. is a well-known Mediterranean plant with important cultural significance in this region. In ancient times, MC was accepted as a symbol of immortality. Maybe due to this belief, it is used during cemetery visits in some regions. Although it is a well-known plant in cosmetics, and there is a lot of studies about its different medical properties, anticancer studies performed using its different extracts or oils are not so much, but increasing. We collected these anticancer property-related studies in this review.

  10. Magnetic polymer nanospheres for anticancer drug targeting

    Energy Technology Data Exchange (ETDEWEB)

    JurIkova, A; Csach, K; Koneracka, M; Zavisova, V; Tomasovicova, N; Lancz, G; Kopcansky, P; Timko, M; Miskuf, J [Institute of Experimental Physics, Slovak Academy of Sciences, 040 01 Kosice (Slovakia); Muckova, M, E-mail: akasard@saske.s [Hameln rds a.s., 900 01 Modra (Slovakia)

    2010-01-01

    Poly(D,L-lactide-co-glycolide) polymer (PLGA) nanospheres loaded with biocom-patible magnetic fluid as a magnetic carrier and anticancer drug Taxol were prepared by the modified nanoprecipitation method with size of 200-250 nm in diameter. The PLGA polymer was utilized as a capsulation material due to its biodegradability and biocompatibility. Taxol as an important anticancer drug was chosen for its significant role against a wide range of tumours. Thermal properties of the drug-polymer system were characterized using thermal analysis methods. It was determined the solubility of Taxol in PLGA nanospheres. Magnetic properties investigated using SQUID magnetometry showed superparamagnetism of the prepared magnetic polymer nanospheres.

  11. Activity of gemifloxacin against quinolone-resistant Streptococcus pneumoniae strains in vitro and in a mouse pneumonia model.

    Science.gov (United States)

    Azoulay-Dupuis, E; Bédos, J P; Mohler, J; Moine, P; Cherbuliez, C; Peytavin, G; Fantin, B; Köhler, T

    2005-03-01

    Gemifloxacin is a novel fluoronaphthyridone quinolone with enhanced in vitro activity against Streptococcus pneumoniae. We investigated the activities of gemifloxacin and trovafloxacin, their abilities to select for resistance in vitro and in vivo, and their efficacies in a mouse model of acute pneumonia. Immunocompetent Swiss mice were infected with 10(5) CFU of a virulent, encapsulated S. pneumoniae strain, P-4241, or its isogenic parC, gyrA, parC gyrA, and efflux mutant derivatives (serotype 3); and leukopenic mice were infected with 10(7) CFU of two poorly virulent clinical strains (serotype 11A) carrying either a parE mutation or a parC, gyrA, and parE triple mutation. The drugs were administered six times every 12 h, starting at either 3 or 18 h postinfection. In vitro, gemifloxacin was the most potent agent against strains with and without acquired resistance to fluoroquinolones. While control mice died within 6 days, gemifloxacin at doses of 25 and 50 mg/kg of body weight was highly effective (survival rates, 90 to 100%) against the wild-type strain and against mutants harboring a single mutation, corresponding to area under the time-versus-serum concentration curve at 24 h (AUC(24))/MIC ratios of 56.5 to 113, and provided a 40% survival rate against a mutant with a double mutation (parC and gyrA). A total AUC(24)/MIC ratio of 28.5 was associated with poor efficacy and the emergence of resistant mutants. Trovafloxacin was as effective as gemifloxacin against mutants with single mutations but did not provide any protection against the mutant with double mutations, despite treatment with a high dose of 200 mg/kg. Gemifloxacin preferentially selected for parC mutants both in vitro and in vivo.

  12. Synthesis, Anticancer and Antibacterial Activity of Salinomycin N-Benzyl Amides

    Directory of Open Access Journals (Sweden)

    Michał Antoszczak

    2014-11-01

    Full Text Available A series of 12 novel monosubstituted N-benzyl amides of salinomycin (SAL was synthesized for the first time and characterized by NMR and FT-IR spectroscopic methods. Molecular structures of three salinomycin derivatives in the solid state were determined using single crystal X-ray method. All compounds obtained were screened for their antiproliferative activity against various human cancer cell lines as well as against the most problematic bacteria strains such as methicillin-resistant Staphylococcus aureus (MRSA and Staphylococcus epidermidis (MRSE, and Mycobacterium tuberculosis. Novel salinomycin derivatives exhibited potent anticancer activity against drug-resistant cell lines. Additionally, two N-benzyl amides of salinomycin revealed interesting antibacterial activity. The most active were N-benzyl amides of SAL substituted at -ortho position and the least anticancer active derivatives were those substituted at the -para position.

  13. Synthesis, anticancer and antibacterial activity of salinomycin N-benzyl amides.

    Science.gov (United States)

    Antoszczak, Michał; Maj, Ewa; Napiórkowska, Agnieszka; Stefańska, Joanna; Augustynowicz-Kopeć, Ewa; Wietrzyk, Joanna; Janczak, Jan; Brzezinski, Bogumil; Huczyński, Adam

    2014-11-25

    A series of 12 novel monosubstituted N-benzyl amides of salinomycin (SAL) was synthesized for the first time and characterized by NMR and FT-IR spectroscopic methods. Molecular structures of three salinomycin derivatives in the solid state were determined using single crystal X-ray method. All compounds obtained were screened for their antiproliferative activity against various human cancer cell lines as well as against the most problematic bacteria strains such as methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus epidermidis (MRSE), and Mycobacterium tuberculosis. Novel salinomycin derivatives exhibited potent anticancer activity against drug-resistant cell lines. Additionally, two N-benzyl amides of salinomycin revealed interesting antibacterial activity. The most active were N-benzyl amides of SAL substituted at -ortho position and the least anticancer active derivatives were those substituted at the -para position.

  14. A Journey Under the Sea: The Quest for Marine Anti-Cancer Alkaloids

    Directory of Open Access Journals (Sweden)

    Nadine Darwiche

    2011-11-01

    Full Text Available The alarming increase in the global cancer death toll has fueled the quest for new effective anti-tumor drugs thorough biological screening of both terrestrial and marine organisms. Several plant-derived alkaloids are leading drugs in the treatment of different types of cancer and many are now being tested in various phases of clinical trials. Recently, marine-derived alkaloids, isolated from aquatic fungi, cyanobacteria, sponges, algae, and tunicates, have been found to also exhibit various anti-cancer activities including anti-angiogenic, anti-proliferative, inhibition of topoisomerase activities and tubulin polymerization, and induction of apoptosis and cytotoxicity. Two tunicate-derived alkaloids, aplidin and trabectedin, offer promising drug profiles, and are currently in phase II clinical trials against several solid and hematologic tumors. This review sheds light on the rich array of anti-cancer alkaloids in the marine ecosystem and introduces the most investigated compounds and their mechanisms of action.

  15. "Ziziphus jujuba": A red fruit with promising anticancer activities

    Directory of Open Access Journals (Sweden)

    Zoya Tahergorabi

    2015-01-01

    Full Text Available Ziziphus jujuba Mill. (Z. jujuba is a traditional herb with a long history of use for nutrition and the treatment of a broad spectrum of diseases. It grows mostly in South and East Asia, as well as in Australia and Europe. Mounting evidence shows the health benefits of Z. jujuba, including anticancer, anti-inflammation, antiobesity, antioxidant, and hepato- and gastrointestinal protective properties, which are due to its bioactive compounds. Chemotherapy, such as with cis-diamminedichloroplatinium (CDDP, cisplatin and its derivatives, is widely used in cancer treatment. It is an effective treatment for human cancers,  including ovarian cancer; however, drug resistance is a major obstacle to successful treatment. A better understanding of the mechanisms and strategies for overcoming chemoresistance can greatly improve therapeutic outcomes for patients. In this review article, the bioactive compounds present in Z. jujuba are explained. The high prevalence of many different cancers worldwide has recently attracted the attention of many researchers. This is why our research group focused on studying the anticancer activity of Z. jujuba as well as its impact on chemoresistance both in vivo and in vitro. We hope that these studies can lead to a promising future for cancer patients.

  16. Paraptosis in the anti-cancer arsenal of natural products.

    Science.gov (United States)

    Lee, Dongjoo; Kim, In Young; Saha, Sharmistha; Choi, Kyeong Sook

    2016-06-01

    Given the problems with malignant cancer cells showing innate and acquired resistance to apoptosis, we need alternative means to induce cell death in cancer. Paraptosis is a type of programmed cell death that is characterized by dilation of the endoplasmic reticulum (ER) and/or mitochondria. Although relatively little is known regarding the molecular basis of paraptosis, the underlying mechanism clearly differs from that of apoptosis. Recent studies have shown that various natural products, including curcumin, celastrol, 15d-PGJ2, ophiobolin A, and paclitaxel, demonstrate anti-cancer effects by inducing the paraptosis-associated cell death, which was commonly characterized by vacuolation derived from the ER. Perturbation of cellular proteostasis due to proteasomal inhibition and disruption of sulfhydryl homeostasis, generation of reactive oxygen species, and/or imbalanced homeostasis of ions (e.g., Ca(2+) and K(+)) appear to contribute to the accumulation of misfolded protein and proteotoxicity in this process. Given the pathophysiological importance of paraptosis and the debate regarding the importance of apoptosis in solid tumor, we need to collect the available knowledge regarding paraptosis and suggest future directions in the field. Here, we review the morphological and biochemical features of paraptosis, the natural products that induce paraptosis-associated cell death, their proposed mechanisms, and the significance of paraptosis as a potential anti-cancer strategy. Such work and future clarifications should enable the development of new strategies for preventing cancer and/or combating malignant cancer.

  17. "Ziziphus jujuba": A red fruit with promising anticancer activities.

    Science.gov (United States)

    Tahergorabi, Zoya; Abedini, Mohammad Reza; Mitra, Moodi; Fard, Mohammad Hassanpour; Beydokhti, Hossein

    2015-01-01

    Ziziphus jujuba Mill. (Z. jujuba) is a traditional herb with a long history of use for nutrition and the treatment of a broad spectrum of diseases. It grows mostly in South and East Asia, as well as in Australia and Europe. Mounting evidence shows the health benefits of Z. jujuba, including anticancer, anti-inflammation, antiobesity, antioxidant, and hepato- and gastrointestinal protective properties, which are due to its bioactive compounds. Chemotherapy, such as with cis-diamminedichloroplatinium (CDDP, cisplatin) and its derivatives, is widely used in cancer treatment. It is an effective treatment for human cancers, including ovarian cancer; however, drug resistance is a major obstacle to successful treatment. A better understanding of the mechanisms and strategies for overcoming chemoresistance can greatly improve therapeutic outcomes for patients. In this review article, the bioactive compounds present in Z. jujuba are explained. The high prevalence of many different cancers worldwide has recently attracted the attention of many researchers. This is why our research group focused on studying the anticancer activity of Z. jujuba as well as its impact on chemoresistance both in vivo and in vitro. We hope that these studies can lead to a promising future for cancer patients.

  18. Marine Invertebrate Metabolites with Anticancer Activities: Solutions to the “Supply Problem”

    Science.gov (United States)

    Gomes, Nelson G. M.; Dasari, Ramesh; Chandra, Sunena; Kiss, Robert; Kornienko, Alexander

    2016-01-01

    Marine invertebrates provide a rich source of metabolites with anticancer activities and several marine-derived agents have been approved for the treatment of cancer. However, the limited supply of promising anticancer metabolites from their natural sources is a major hurdle to their preclinical and clinical development. Thus, the lack of a sustainable large-scale supply has been an important challenge facing chemists and biologists involved in marine-based drug discovery. In the current review we describe the main strategies aimed to overcome the supply problem. These include: marine invertebrate aquaculture, invertebrate and symbiont cell culture, culture-independent strategies, total chemical synthesis, semi-synthesis, and a number of hybrid strategies. We provide examples illustrating the application of these strategies for the supply of marine invertebrate-derived anticancer agents. Finally, we encourage the scientific community to develop scalable methods to obtain selected metabolites, which in the authors’ opinion should be pursued due to their most promising anticancer activities. PMID:27213412

  19. Marine Invertebrate Metabolites with Anticancer Activities: Solutions to the “Supply Problem”

    Directory of Open Access Journals (Sweden)

    Nelson G. M. Gomes

    2016-05-01

    Full Text Available Marine invertebrates provide a rich source of metabolites with anticancer activities and several marine-derived agents have been approved for the treatment of cancer. However, the limited supply of promising anticancer metabolites from their natural sources is a major hurdle to their preclinical and clinical development. Thus, the lack of a sustainable large-scale supply has been an important challenge facing chemists and biologists involved in marine-based drug discovery. In the current review we describe the main strategies aimed to overcome the supply problem. These include: marine invertebrate aquaculture, invertebrate and symbiont cell culture, culture-independent strategies, total chemical synthesis, semi-synthesis, and a number of hybrid strategies. We provide examples illustrating the application of these strategies for the supply of marine invertebrate-derived anticancer agents. Finally, we encourage the scientific community to develop scalable methods to obtain selected metabolites, which in the authors’ opinion should be pursued due to their most promising anticancer activities.

  20. Adsorption of quinolone, tetracycline, and penicillin antibiotics from aqueous solution using activated carbons: Review.

    Science.gov (United States)

    Ahmed, Muthanna J

    2017-03-01

    Antibiotics, an important type of pharmaceutical pollutant, have attracted many researchers to the study of their removal from aqueous solutions. Activated carbon (AC) has been widely used as highly effective adsorbent for antibiotics because of its large specific surface area, high porosity, and favorable pore size distribution. In this article, the adsorption performance of AC towards three major types of antibiotics such as tetracyclines, quinolones, and penicillins were reviewed. According to collected data, maximum adsorption capacities of 1340.8, 638.6, and 570.4mg/g were reported for tetracyclines, quinolones, and penicillins, respectively. The values of 1/n for Freundlich isotherm were less than unity, suggesting that the adsorption was nonlinear and favorable. Adsorption kinetics followed closely the pseudo-second-order model and analysis using the Weber-Morris model revealed that the intra-particle diffusion was not the only rate controlling step. AC adsorption demonstrated superior performance for all selected drugs, thus being efficient technology for treatment of these pollutants.

  1. Structure Based In Silico Analysis of Quinolone Resistance in Clinical Isolates of Salmonella Typhi from India

    Science.gov (United States)

    Sharma, Priyanka; Sharma, Sujata; Singh, Tej P.; Kapil, Arti; Kaur, Punit

    2015-01-01

    Enteric fever is a major cause of morbidity in several parts of the Indian subcontinent. The treatment for typhoid fever majorly includes the fluoroquinolone group of antibiotics. Excessive and indiscriminate use of these antibiotics has led to development of acquired resistance in the causative organism Salmonella Typhi. The resistance towards fluoroquinolones is associated with mutations in the target gene of DNA Gyrase. We have estimated the Minimum Inhibitory Concentration (MIC) of commonly used fluoroquinolone representatives from three generations, ciprofloxacin, ofloxacin, levofloxacin and moxifloxacin, for 100 clinical isolates of Salmonella Typhi from patients in the Indian subcontinent. The MICs have been found to be in the range of 0.032 to 8 μg/ml. The gene encoding DNA Gyrase was subsequently sequenced and point mutations were observed in DNA Gyrase in the quinolone resistance determining region comprising Ser83Phe/Tyr and Asp87Tyr/Gly. The binding ability of these four fluoroquinolones in the quinolone binding pocket of wild type as well as mutant DNA Gyrase was computationally analyzed by molecular docking to assess their differential binding behaviour. This study has revealed that mutations in DNA Gyrase alter the characteristics of the binding pocket resulting in the loss of crucial molecular interactions and consequently decrease the binding affinity of fluoroquinolones with the target protein. The present study assists in understanding the underlying molecular and structural mechanism for decreased fluoroquinolone susceptibility in clinical isolates as a consequence of mutations in DNA Gyrase. PMID:25962113

  2. Structure based in silico analysis of quinolone resistance in clinical isolates of Salmonella Typhi from India.

    Directory of Open Access Journals (Sweden)

    Manoj Kumar

    Full Text Available Enteric fever is a major cause of morbidity in several parts of the Indian subcontinent. The treatment for typhoid fever majorly includes the fluoroquinolone group of antibiotics. Excessive and indiscriminate use of these antibiotics has led to development of acquired resistance in the causative organism Salmonella Typhi. The resistance towards fluoroquinolones is associated with mutations in the target gene of DNA Gyrase. We have estimated the Minimum Inhibitory Concentration (MIC of commonly used fluoroquinolone representatives from three generations, ciprofloxacin, ofloxacin, levofloxacin and moxifloxacin, for 100 clinical isolates of Salmonella Typhi from patients in the Indian subcontinent. The MICs have been found to be in the range of 0.032 to 8 μg/ml. The gene encoding DNA Gyrase was subsequently sequenced and point mutations were observed in DNA Gyrase in the quinolone resistance determining region comprising Ser83Phe/Tyr and Asp87Tyr/Gly. The binding ability of these four fluoroquinolones in the quinolone binding pocket of wild type as well as mutant DNA Gyrase was computationally analyzed by molecular docking to assess their differential binding behaviour. This study has revealed that mutations in DNA Gyrase alter the characteristics of the binding pocket resulting in the loss of crucial molecular interactions and consequently decrease the binding affinity of fluoroquinolones with the target protein. The present study assists in understanding the underlying molecular and structural mechanism for decreased fluoroquinolone susceptibility in clinical isolates as a consequence of mutations in DNA Gyrase.

  3. [Effect of pazufloxacin mesilate, a new quinolone antibacterial agent, for intravenous use on QT interval].

    Science.gov (United States)

    Fukuda, Hitoshi; Morita, Yukie; Shiotani, Norio; Mizuo, Midori; Komae, Norihisa

    2004-08-01

    The potential for QT interval prolongation of pazufloxacin mesilate (PZFX mesilate), a new quinolone antibacterial agent for intravenous use, was investigated by in vitro and in vivo electrophysiology studies. Following results were obtained. In vitro electrophysiology study using guinea pig papillary muscles: PZFX mesilate (30-300 microM) had no effects on resting membrane potential (RMP), action potential amplitude (APA) and action potential duration (APD). Reference quinolones, sparfloxacin (3-30 microM) and moxifloxacin (10-100 microM), had no effects on RMP and APA, but significantly prolonged APD at more than 3 and 10 microM, respectively, while ciprofloxacin (10-100 microM) had no effect on each parameter. In vivo electrophysiology study using anesthetized dogs: PZFX mesilate had no effects on electrocardiograph parameter (PR interval, QRS interval, QT interval and QTc) after intravenous administration of 3-30 mg/kg. These results suggest that PZFX mesilate has low potential for QT interval prolongation.

  4. Increasing resistance to quinolones: A four-year prospective study of urinary tract infection pathogens

    Directory of Open Access Journals (Sweden)

    Orhiosefe Omigie

    2009-08-01

    Full Text Available Orhiosefe Omigie, Lawrence Okoror, Patience Umolu, Gladys IkuuhDepartment of Microbiology, Ambrose Alli University, Ekpoma, NigeriaAbstract: A four-year prospective study was carried out to determine the incidence and rate of development of resistance by common urinary tract infection (UTI pathogens to quinolone antimicrobial agents. Results show that there is high intrinsic resistance to the quinolones among strains of Pseudomonas aeruginosa (43.4%, Escherichia coli (26.3%, and Proteus spp. (17.1%. Over four years, rising rates of resistance were observed in P. aeruginosa (14.6% increase, Staphylococcus aureus (9.8%, and E. coli (9.7%. The highest potency was exhibited by ciprofloxacin (91.2%, levofloxacin (89.2%, and moxifloxacin (85.1%, while there were high rates of resistance to nalidixic acid (51.7% and pefloxacin (29.0%. Coliforms, particularly E. coli (>45%, remain the most prevalent causative agents of UTI while females within the age range of 20–50 years were most vulnerable to UTI.Keywords: UTI, microorganisms, antibiotics, resistance

  5. Bacterial plasmid-mediated quinolone resistance genes in aquatic environments in China

    Science.gov (United States)

    Yan, Lei; Liu, Dan; Wang, Xin-Hua; Wang, Yunkun; Zhang, Bo; Wang, Mingyu; Xu, Hai

    2017-01-01

    Emerging antimicrobial resistance is a major threat to human’s health in the 21st century. Understanding and combating this issue requires a full and unbiased assessment of the current status on the prevalence of antimicrobial resistance genes and their correlation with each other and bacterial groups. In aquatic environments that are known reservoirs for antimicrobial resistance genes, we were able to reach this goal on plasmid-mediated quinolone resistance (PMQR) genes that lead to resistance to quinolones and possibly also to the co-emergence of resistance to β-lactams. Novel findings were made that qepA and aac-(6′)-Ib genes that were previously regarded as similarly abundant with qnr genes are now dominant among PMQR genes in aquatic environments. Further statistical analysis suggested that the correlation between PMQR and β-lactam resistance genes in the environment is still weak, that the correlations between antimicrobial resistance genes could be weakened by sufficient wastewater treatment, and that the prevalence of PMQR has been implicated in environmental, pathogenic, predatory, anaerobic, and more importantly, human symbiotic bacteria. This work provides a comprehensive analysis of PMQR genes in aquatic environments in Jinan, China, and provides information with which combat with the antimicrobial resistance problem may be fought. PMID:28094345

  6. Analysis of quinolones by voltage-assisted liquid-phase microextraction combined with LC-MS.

    Science.gov (United States)

    Wang, Mi-Hung; Wang, Shu-Ping

    2012-03-01

    The method of liquid-phase microextraction assisted with voltage was developed and applied on determination of quinolones in water sample in this study. Both of the reproducibility and extraction time were improved with the aid of applying voltage. Four analytes in neutral state such as cinoxacin, oxolinic acid, nalidixic acid, and flumequine were extracted from a sample solution at pH 2.0, through a polypropylene hollow fiber which was immobilized with 2-octanone, and then into a 25 μL of the acceptor phase of 40 mM borate buffer at pH 10.0 by applying voltage of 100 V. Subsequently, the acceptor solution was directly subjected to analysis by LC-MS. The performance of the method for four quinolones was also evaluated. Linearity was obtained in the range of 1.0-25.0 ng/mL with R(2) > 0.996. Limits of detection were below 0.6 ng/mL, and recoveries of water sample were ranged from 90.8 to 109.6%.

  7. Structure based in silico analysis of quinolone resistance in clinical isolates of Salmonella Typhi from India.

    Science.gov (United States)

    Kumar, Manoj; Dahiya, Sushila; Sharma, Priyanka; Sharma, Sujata; Singh, Tej P; Kapil, Arti; Kaur, Punit

    2015-01-01

    Enteric fever is a major cause of morbidity in several parts of the Indian subcontinent. The treatment for typhoid fever majorly includes the fluoroquinolone group of antibiotics. Excessive and indiscriminate use of these antibiotics has led to development of acquired resistance in the causative organism Salmonella Typhi. The resistance towards fluoroquinolones is associated with mutations in the target gene of DNA Gyrase. We have estimated the Minimum Inhibitory Concentration (MIC) of commonly used fluoroquinolone representatives from three generations, ciprofloxacin, ofloxacin, levofloxacin and moxifloxacin, for 100 clinical isolates of Salmonella Typhi from patients in the Indian subcontinent. The MICs have been found to be in the range of 0.032 to 8 μg/ml. The gene encoding DNA Gyrase was subsequently sequenced and point mutations were observed in DNA Gyrase in the quinolone resistance determining region comprising Ser83Phe/Tyr and Asp87Tyr/Gly. The binding ability of these four fluoroquinolones in the quinolone binding pocket of wild type as well as mutant DNA Gyrase was computationally analyzed by molecular docking to assess their differential binding behaviour. This study has revealed that mutations in DNA Gyrase alter the characteristics of the binding pocket resulting in the loss of crucial molecular interactions and consequently decrease the binding affinity of fluoroquinolones with the target protein. The present study assists in understanding the underlying molecular and structural mechanism for decreased fluoroquinolone susceptibility in clinical isolates as a consequence of mutations in DNA Gyrase.

  8. Lack of efflux mediated quinolone resistance in Salmonella enterica serovars Typhi and Paratyphi A

    Directory of Open Access Journals (Sweden)

    Sylvie eBaucheron

    2014-01-01

    Full Text Available Salmonella enterica serovars Typhi and Paratyphi A isolates from human patients in France displaying different levels of resistance to quinolones or fluoroquinolones were studied for resistance mechanisms to these antimicrobial agents. All resistant isolates carried either single or multiple target gene mutations (i.e. in gyrA, gyrB, or parC correlating with the resistance levels observed. Active efflux, through upregulation of multipartite efflux systems, has also been previously reported as contributing mechanism for other serovars. Therefore, we investigated also the occurrence of non-target gene mutations in regulatory regions affecting efflux pump expression. However, no mutation was detected in these regions in both Typhi and Paratyphi isolates of this study. Besides, no overexpression of the major efflux systems was observed for these isolates. Nevertheless, a large deletion of 2334 bp was identified in the acrS-acrE region of all S. Typhi strains but which did not affect the resistance phenotype. As being specific to S. Typhi, this deletion could be used for specific molecular detection purposes. In conclusion, the different levels of quinolone or FQ resistance in both S. Typhi and S. Paratyphi A seem to rely only on target modifications.

  9. Quantitative determination of quinolones residues in milk by HPLC-FLD

    Directory of Open Access Journals (Sweden)

    Marilena Gili

    2012-10-01

    Full Text Available Veterinary drugs have become an integral part of the livestock production and play an important role in maintenance of animal welfare. The use of veterinary medicines may be cause of the presence of drug residues in animal food products if appropriate withdrawal periods are not respected or if contaminated feeds are used. This work presents the development of an HPLC-FLD method for the quantitative de-tection of eight quinolones – norfloxacin, ciprofloxacin, danofloxacin, enrofloxacin, difloxacin, oxolinic acid, nalidixic acid, flumequine– in bovine milk. After deproteination and extraction with a metaphos-phoric acid 1% w/v / methanol / acetonitrile (60/20/20 v/v/v solution, the sample is partially evaporated and cleaned up on a reversed phase SPE cartridge.The extract is analyzed using an high performance liquid chromatograph with fluorescence detector. Mean recovery ranged between 65% - 88%. All the an-alytes can be identified and quantified in the concentration range 15 - 60 μg/Kg for danofloxacin and 25 - 150 μg/Kg for the other quinolones.

  10. Genotypic characterization of quinolone resistant-Escherichia coli isolates from retail food in Morocco.

    Science.gov (United States)

    Nayme, Kaotar; Barguigua, Abouddihaj; Bouchrif, Brahim; Karraouan, Bouchra; El Otmani, Fatima; Elmdaghri, Naima; Zerouali, Khalid; Timinouni, Mohammed

    2017-02-01

    This study was conducted to assess the retail food as a possible vehicle for antimicrobial resistant, particularly quinolones resistant and pathogenic Escherichia coli. We determined the prevalence and characteristics of nalidixic acid (Nal) resistant E. coli isolates from diverse retail food samples. In all, 70 (28%) of 250 E. coli isolates studied were Nal-resistant E. coli and 91% of these were multi-drug resistant. Plasmid mediated quinolone resistance genes were identified in 32 isolates, including aac(6')-Ib-cr (n = 16), qnrS1 (n = 11) and qnrB19 (n = 7). Mutations in gyr A and par C genes were detected among 80% of the isolates, and the isolates showed substitution Ser83-Leu and Asp87-Asn in gyrA and Ser80-Ile in parC. In addition, three different gene cassettes were identified (aadA1, aadA7, aac(3)-Id) in 18%. Virulence-associated genes stx1, eae, sfa, hlyA and stx2 were found in six (8%), three (4%), two (3%), three (4%) and three (4%) isolates, respectively. E. coli isolates of phylogenetic group A were dominant (64%, 45/70). Pulsed field gel electrophoresis revealed none epidemiological relationship between these isolates. The results of this work report the higher frequency of Nal-resistant E. coli isolates from Moroccan retail food samples including MDR and pathogenic isolates.

  11. Methods for predicting anti-cancer response

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention relates to methods for predicting response of a cancer in a subject to anti-cancer therapies based upon a determination and analysis of a chromosomal aberration score, such as the number of allelic imbalance or the number of telomeric allelic imbalance in the chromosomes...

  12. Cell death signaling and anticancer therapy

    Directory of Open Access Journals (Sweden)

    Lorenzo eGalluzzi

    2011-05-01

    Full Text Available For a long time, it was commonly believed that efficient anticancer regimens would either trigger the apoptotic demise of tumor cells or induce a permanent arrest in the G1 phase of the cell cycle, i.e., senescence. The recent discovery that necrosis can occur in a regulated fashion and the increasingly more precise characterization of the underlying molecular mechanisms have raised great interest, as non-apoptotic pathways might be instrumental to circumvent the resistance of cancer cells to conventional, pro-apoptotic therapeutic regimens. Moreover, it has been shown that some anticancer regimens engage lethal signaling cascades that can ignite multiple oncosuppressive mechanisms, including apoptosis, necrosis and senescence. Among these signaling pathways is mitotic catastrophe, whose role as a bona fide cell death mechanism has recently been reconsidered. Thus, anticancer regimens get ever more sophisticated, and often distinct strategies are combined to maximize efficacy and minimize side effects. In this review, we will discuss the importance of apoptosis, necrosis and mitotic catastrophe in the response of tumor cells to the most common clinically employed and experimental anticancer agents.

  13. Detection of mutations in mtrR gene in quinolone resistant strains of N.gonorrhoeae isolated from India

    Directory of Open Access Journals (Sweden)

    S V Kulkarni

    2015-01-01

    Full Text Available Background and Objectives: Emergence of multi-drug resistant Neisseria gonorrhoeae resulting from new genetic mutation is a serious threat in controlling gonorrhea. This study was undertaken to identify and characterise mutations in the mtrR genes in N.gonorrhoeae isolates resistant to six different antibiotics in the quinolone group. Materials and Methods: The Minimum inhibitory concentrations (MIC of five quinolones for 64 N.gonorrhoeae isolates isolated during Jan 2007-Jun 2009 were determined by E-test method. Mutations in MtrR loci were examined by deoxyribonucleic acid (DNA sequencing. Results: The proportion of N.gonorrhoeae strains resistant to anti-microbials was 98.4% for norfloxacin and ofloxacin, 96.8% for enoxacin and ciprofloxacin, 95.3% for lomefloxacin. Thirty-one (48.4% strains showed mutation (single/multiple in mtrR gene. Ten different mutations were observed and Gly-45 → Asp, Tyr-105 → His being the most common observed mutation. Conclusion: This is the first report from India on quinolone resistance mutations in MtrRCDE efflux system in N.gonorrhoeae. In conclusion, the high level of resistance to quinolone and single or multiple mutations in mtrR gene could limit the drug choices for gonorrhoea.

  14. Risk factors for quinolone-resistant Escherichia coli in feces from preweaned dairy calves and postpartum dairy cows.

    Science.gov (United States)

    Duse, Anna; Waller, Karin Persson; Emanuelson, Ulf; Unnerstad, Helle Ericsson; Persson, Ylva; Bengtsson, Björn

    2015-09-01

    Quinolone resistance may emerge in gut bacteria (e.g., in Escherichia coli) of animals. Such bacteria could cause infections in the animal itself or be transmitted to humans via the food chain. Quinolone resistance is also observed in fecal E. coli of healthy dairy cattle, but the prevalence varies between farms, not solely as a result of varying degree of fluoroquinolone exposure. The objective of this study was to identify risk factors for the fecal shedding of quinolone-resistant E. coli (QREC) from dairy calves and postpartum cows. Rectal swabs from 15 preweaned calves and 5 postpartum cows per farm were collected on 23 Swedish dairy farms to determine the prevalence of QREC. Risk factors for the shedding of QREC were investigated using multivariable statistical models. Quinolone-resistant E. coli were found on all but one farm. Factors associated with QREC shedding by calves were being younger than 18 d, being fed milk from cows treated with antimicrobials, recent use of fluoroquinolones in the herd, carriage of QREC by postpartum cows, and using the calving area never or rarely as a sick pen compared with often. Factors associated with QREC shedding by cows were calving in group pens or freestalls compared with single pens or tiestalls, purchasing cattle, sharing animal transports with other farmers, and poor farm hygiene. Proper biosecurity and improved hygiene, as well as minimizing fluoroquinolone exposure and waste milk feeding, may be important factors to reduce the burden of QREC on dairy farms.

  15. Progress in research on quinolone antibacterials%喹诺酮类抗菌药物研究新进展

    Institute of Scientific and Technical Information of China (English)

    蒋晓磊; 崔玉彬; 曹胜华

    2011-01-01

    This article has reviewed progress in research on quinolone antibacterials in recent years,which consisted of newly launched products, agents in clinical trials and future development of this kind of drugs. It focused on some clinical promising candidates. Among these drugs, delafloxacin would be the most potential candidate.Moreover it introduced new fields of the future development, including modifying side chain, quinolone-like compounds, antibacterial quinolone hybrids and anti-TB quinolone-drug conjugates.%本文简述了喹诺酮类药物近几年的研究进展,分为上市药物、临床试验药物和未来发展趋势三部分,对目前处于临床研究阶段的药物做了重点讲述,其中delafloxacin是最有希望的喹诺酮类候选药物,同时介绍了喹诺酮类抗菌药物的未来发展方向,即侧链修饰、喹诺酮类似物、喹诺酮杂合物和TB药物与喹诺酮扼合物.

  16. Rational use of quinolones antibiotics%合理应用喹诺酮类抗菌药物

    Institute of Scientific and Technical Information of China (English)

    宋惠珠

    2011-01-01

    目的 了解喹诺酮类抗菌药物的作用机制,不良反应及使用时的注意事项. 方法 对喹诺酮类抗菌药物在临床使用中的注意事项及所涉及的不良反应进行汇总. 结果 随着临床使用喹诺酮类抗菌药物的增加,药物的不良反应也随着上升,其不良反应发生率<2.0%,肾损害的发生率为0.9%~4.3%. 结论 在广泛应用喹诺酮类抗菌药物的同时,要更多地关注其安全性.%OBJECTIVE To understand the mechanism of quinolones, adverse reactions and precautions when using.METHODS The precautions of quinolones in clinical use and the adverse reactions involved were aggregated.RESULTS With the increased clinical use of quinolones, the incidence of adverse drug reactions was increased more than <2.0%. CONCLUSION In the widely use of quinolones antibiotics, their safety should be more concerned about.

  17. Distribution and risk assessment of quinolone antibiotics in the soils from organic vegetable farms of a subtropical city, Southern China.

    Science.gov (United States)

    Wu, Xiao-Lian; Xiang, Lei; Yan, Qing-Yun; Jiang, Yuan-Neng; Li, Yan-Wen; Huang, Xian-Pei; Li, Hui; Cai, Quan-Ying; Mo, Ce-Hui

    2014-07-15

    Organic fertilizer or manure containing antibiotics has been widely used in organic farms, but the distribution and potential impacts of antibiotics to the local environment are not well understood. In this study, four quinolone antibiotics in soil samples (n=69) from five organic vegetable farms in a subtropical city, Southern China, were analyzed using high performance liquid chromatography-tandem mass spectrometry. Our results indicated that quinolone compounds were ubiquitous in soil samples (detection frequency>97% for all compounds), and their concentrations ranged from not detectable to 42.0 μg/kg. Among the targets, enrofloxacin (ENR) was the dominant compound, followed by ciprofloxacin (CIP) and norfloxacin (NOR). The average total concentrations of four compounds in the soils were affected by vegetable types and species cultivated, decreasing in the order of fruit>rhizome>leaf vegetables. Moreover, the average concentrations of quinolone compounds (except ENR) in open-field soils were higher than those in greenhouse soils. The concentrations of quinolone antibiotics in this study were lower than the ecotoxic effect trigger value (100 μg/kg) proposed by the Veterinary Medicine International Coordination commission. Risk assessment based on the calculated risk quotients indicated that NOR, CIP, and ENR posed mainly medium to low risks to bacteria.

  18. A Facile Solid Phase Synthesis of 2—Alkylthio—4(1H)—quinolones

    Institute of Scientific and Technical Information of China (English)

    TANG,Jing; WU,Ming-Guang; HUANG,Xian

    2003-01-01

    The resin-bound cyclic malonic acid ester 2 reacted with aryl isothiocyanate and alkyl halides to afford the key intermediate arylthioaminomethylene cyclic malonic ester resin 3.Subsequently,resin 3 proceeded thermal cyclizaiton giving the 2-alkylthio-4(1H)-quinolones in good yields and excellent purties.

  19. Quinolones control in milk and eggs samples by liquid chromatography using a surfactant-mediated mobile phase.

    Science.gov (United States)

    Rambla-Alegre, M; Collado-Sánchez, M A; Esteve-Romero, J; Carda-Broch, S

    2011-05-01

    Four quinolones (danofloxacin, difloxacin, flumequine and marbofloxacin) were determined in milk and egg samples by a simplified high-performance liquid chromatographic procedure using a micellar mobile phase. No extraction was needed to precipitate the proteins from the matrices since they were solubilised in micelles. The only pretreatment steps required were homogenisation, dilution and filtration before injecting the sample into the chromatographic system. An adequate resolution of the quinolones was achieved by a chemometrics approach where retention was modelled as a first step using the retention factors in only five mobile phases. Afterwards, an optimisation criterion was applied to consider the position and shape of the chromatographic peaks. Analytical separation involved a C18 reversed-phase column, a hybrid micellar mobile phase of 0.05 M sodium dodecyl sulphate, 10% (v/v) butanol and 0.5% (v/v) triethylamine buffered at pH 3 and fluorimetric detection. Quinolones were eluted in less than 15 min without the protein band or other endogenous compounds from the food matrices interfering. The calculated relevant validation parameters, e.g., decision limit (CC(α)), detection capability (CC(β)), repeatability, within-laboratory reproducibility, recoveries and robustness, were acceptable and complied with European Commission Decision 2002/657/EC. Finally, the proposed method was successfully employed in quantifying the four quinolones in spiked egg and milk samples.

  20. Fluorimetric study of the interaction between human serum albumin and quinolones-terbium complex and its application

    Science.gov (United States)

    Wang, Yusheng; Feng, Lin; Jiang, Chongqiu

    2005-10-01

    A highly sensitive spectrofluorimetric method is proposed for determination of human serum albumin (HSA) and some quinolone drugs. Using quinolones-terbium (Tb 3+) complex as a fluorescent probe, in the buffer solution of pH 7.8, HSA can remarkably enhance the fluorescence intensity of the quinolones-Tb 3+ complex at 545 nm and the enhanced fluorescence intensity of Tb 3+ ion is in proportion to the concentration of HSA and quinolone drugs. Optimum conditions for the determination of HSA were also investigated. The linear ranges and limits of detection are 8.0 × 10 -9 to 8.0 × 10 -8 mol L -1, 4.20 × 10 -9 mol L -1 (for HSA); 1.0 × 10 -6 to 4.0 × 10 -6 mol L -1, 1.87 × 10 -8 mol L -1 (for norfloxacin) and 1.0 × 10 -7 to 1.0 × 10 -6 mol L -1, 4.82 × 10 -8 mol L -1 (for enoxacine), respectively. This method is simple, practical and relatively free interference from coexisting substances, as well as much more sensitive than most of the existing assays.

  1. Development of an optical surface plasmon resonance biosensor assay for (fluoro) quinolones in egg, fish, and poultry meat

    NARCIS (Netherlands)

    Huet, A.C.; Charlier, C.; Singh, G.; Benrejeb Godefroy, S.; Leivo, J.; Vehniainen, M.; Nielen, M.W.F.; Weigel, S.; Delahaut, P.

    2008-01-01

    The aim of this study was to develop an optical biosensor inhibition immunoassay, based on the surface plasmon resonance (SPR) principle, for use as a screening test for 13 (fluoro)quinolones, including flumequine, used as veterinary drugs in food-producing animals. For this, we immobilised various

  2. Validation of an optical surface plasmon resonance biosensor assay for screening (fluoro)quinolones in egg, fish and poultry

    NARCIS (Netherlands)

    Huet, A.C.; Charlier, C.; Weigel, S.; Benrejeb Godefroy, S.; Delahaut, P.

    2009-01-01

    A surface plasmon resonance biosensor immunoassay has been developed for multi-residue determination of 13 (fluoro)quinolone antibiotics in poultry meat, eggs and fish. The following performance characteristics were determined according to the guidelines laid down for screening assay validation in E

  3. Orally bioavailable 6-chloro-7-methoxy-4(1H)-quinolones efficacious against multiple stages of Plasmodium.

    Science.gov (United States)

    Cross, R Matthew; Flanigan, David L; Monastyrskyi, Andrii; LaCrue, Alexis N; Sáenz, Fabián E; Maignan, Jordany R; Mutka, Tina S; White, Karen L; Shackleford, David M; Bathurst, Ian; Fronczek, Frank R; Wojtas, Lukasz; Guida, Wayne C; Charman, Susan A; Burrows, Jeremy N; Kyle, Dennis E; Manetsch, Roman

    2014-11-13

    The continued proliferation of malaria throughout temperate and tropical regions of the world has promoted a push for more efficacious treatments to combat the disease. Unfortunately, more recent remedies such as artemisinin combination therapies have been rendered less effective due to developing parasite resistance, and new drugs are required that target the parasite in the liver to support the disease elimination efforts. Research was initiated to revisit antimalarials developed in the 1940s and 1960s that were deemed unsuitable for use as therapeutic agents as a result of poor understanding of both physicochemical properties and parasitology. Structure-activity and structure-property relationship studies were conducted to generate a set of compounds with the general 6-chloro-7-methoxy-2-methyl-4(1H)-quinolone scaffold which were substituted at the 3-position with a variety of phenyl moieties possessing various properties. Extensive physicochemical evaluation of the quinolone series was carried out to downselect the most promising 4(1H)-quinolones, 7, 62, 66, and 67, which possessed low-nanomolar EC50 values against W2 and TM90-C2B as well as improved microsomal stability. Additionally, in vivo Thompson test results using Plasmodium berghei in mice showed that these 4(1H)-quinolones were efficacious for the reduction of parasitemia at >99% after 6 days.

  4. Analysis of the gyrA gene of clinical Yersinia ruckeri isolates with reduced susceptibility to quinolones.

    Science.gov (United States)

    Gibello, Alicia; Porrero, M Concepción; Blanco, M Mar; Vela, Ana I; Liébana, Pilar; Moreno, Miguel A; Fernández-Garayzábal, José F; Domínguez, Lucas

    2004-01-01

    Antimicrobial susceptibility of seven clinical strains of Yersinia ruckeri representative of those isolated between 1994 and 2002 from a fish farm with endemic enteric redmouth disease was studied. All isolates displayed indistinguishable pulsed-field gel electrophoresis restriction patterns, indicating that they represented a single strain. However, considering both inhibition zone diameters (IZD) and MICs, the isolates recovered in 2001-2002 formed a separate cluster with lower levels of susceptibility to all the quinolones tested, especially nalidixic acid (NA) and oxolinic acid (OA), compared with the isolates recovered between 1994 and 1998. Analysis of the PCR product of the quinolone resistance-determining region of the gyrA gene from clinical isolates of Y. ruckeri with reduced susceptibility to OA and NA revealed a single amino acid substitution, Ser-83 to Arg-83 (Escherichia coli numbering). Identical substitution was observed in induced OA-resistant mutant strains, which displayed IZD and MICs of quinolones similar to those of the clinical isolates of Y. ruckeri with reduced susceptibility to these antimicrobial agents. These data indicate in that for Y. ruckeri, the substitution of Ser by Arg at position 83 of the gyrA gene is associated with reduced susceptibility to quinolones.

  5. Quinolone resistance and ESBL/AmpC’s in commensal Escherichia coli in veal calves : prevalence and molecular characterization

    NARCIS (Netherlands)

    Hordijk, J.

    2013-01-01

    In this thesis the prevalence and molecular characteristics of resistance to (fluoro)quinolones and Extended Spectrum Cephalosporins (ESC) in veal calves were described using Escherichia coli as an indicator organism. Ciprofloxacin and nalidixic acid were used as indicator antimicrobials for quinolo

  6. Quinolone- and ß-lactam-resistance in Escherichia coli from Danish and Italian broiler flocks

    DEFF Research Database (Denmark)

    Bortolaia, Valeria; Guardabassi, Luca; Bisgaard, Magne

    Frederiksberg C, Denmark 2Dipartimento di Sanità Pubblica Veterinaria e Patologia Animale, Facoltà di Medicina Veterinaria, Università di Bologna, 40064 Ozzano Emilia (BO), Italy   The prevalence of quinolone- and ß-lactam-resistant E. coli was investigated among broiler flocks in Denmark and Italy. In Denmark...

  7. Studies on the antagonistic action between chloramphenicol and quinolones with presence of bovine serum albumin by fluorescence spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Liu Baosheng, E-mail: lbs@hbu.edu.c [Key Laboratory of Medical Chemistry and Molecular Diagnosis, Ministry of Education, Center of Physics and Chemistry, Hebei University, Baoding 071002 (China); Zhao Fengli; Xue Chunli; Wang Jing; Lu Yunkai [Key Laboratory of Medical Chemistry and Molecular Diagnosis, Ministry of Education, Center of Physics and Chemistry, Hebei University, Baoding 071002 (China)

    2010-05-15

    Chloramphenicol (CHL) and quinolone drugs like ofloxacin (OFLX), lomefloxacin (LMX) and ciprofloxacin (CPFX) can all quench the fluorescence of bovine serum albumin (BSA) in the aqueous solution of pH=7.40. This quenching effect becomes more significant when CHL and quinolone drugs coexist. Based on this, further studies on the interactions between CHL and quinolone drugs using fluorescence spectrum are established. The results showed that the interaction between the drugs would increase the binding constant and binding stability of the drug and protein, thus reducing the amount of drugs transported to their targets. Therefore, free drug concentration at targets would decrease, reducing the efficacy of the drugs. It indicated that there exists antagonistic action between drugs. The results also showed that the quenching mechanism of BSA by the drugs is a static procedure. The number of binding sites is 1 in various systems. Due to the existence of the antagonistic action between drugs, the binding distance r is reduced. Studies utilizing synchronous spectra showed that the antagonistic action between the drugs would affect the conformation of BSA, making protein molecules extend and hydrophobic decrease. The order of antagonistic action between CHL and quinolone drugs is: CPFX>OFLX>LMX with presence of BSA.

  8. Shifts in the Antibiotic Susceptibility, Serogroups, and Clonal Complexes of Neisseria meningitidis in Shanghai, China: A Time Trend Analysis of the Pre-Quinolone and Quinolone Eras.

    Directory of Open Access Journals (Sweden)

    Mingliang Chen

    2015-06-01

    Full Text Available Fluoroquinolones have been used broadly since the end of the 1980s and have been recommended for Neisseria meningitidis prophylaxis since 2005 in China. The aim of this study was to determine whether and how N. meningitidis antimicrobial susceptibility, serogroup prevalence, and clonal complex (CC prevalence shifted in association with the introduction and expanding use of quinolones in Shanghai, a region with a traditionally high incidence of invasive disease due to N. meningitidis.A total of 374 N. meningitidis isolates collected by the Shanghai Municipal Center for Disease Control and Prevention between 1965 and 2013 were studied. Shifts in the serogroups and CCs were observed, from predominantly serogroup A CC5 (84% in 1965-1973 to serogroup A CC1 (58% in 1974-1985, then to serogroup C or B CC4821 (62% in 2005-2013. The rates of ciprofloxacin nonsusceptibility in N. meningitidis disease isolates increased from 0% in 1965-1985 to 84% (31/37 in 2005-2013 (p < 0.001. Among the ciprofloxacin-nonsusceptible isolates, 87% (27/31 were assigned to either CC4821 (n = 20 or CC5 (n = 7. The two predominant ciprofloxacin-resistant clones were designated ChinaCC4821-R1-C/B and ChinaCC5-R14-A. The ChinaCC4821-R1-C/B clone acquired ciprofloxacin resistance by a point mutation, and was present in 52% (16/31 of the ciprofloxacin-nonsusceptible disease isolates. The ChinaCC5-R14-A clone acquired ciprofloxacin resistance by horizontal gene transfer, and was found in 23% (7/31 of the ciprofloxacin-nonsusceptible disease isolates. The ciprofloxacin nonsusceptibility rate was 47% (7/15 among isolates from asymptomatic carriers, and nonsusceptibility was associated with diverse multi-locus sequence typing profiles and pulsed-field gel electrophoresis patterns. As detected after 2005, ciprofloxacin-nonsusceptible strains were shared between some of the patients and their close contacts. A limitation of this study is that isolates from 1986-2004 were not available

  9. Emergence of quinolone resistance among extended-spectrum beta-lactamase-producing Enterobacteriaceae in the Central African Republic: genetic characterization

    Directory of Open Access Journals (Sweden)

    Frank Thierry

    2011-08-01

    Full Text Available Abstract Background Cross-resistance to quinolones and beta-lactams is frequent in Enterobacteriaceae, due to the wide use of these antibiotics clinically and in the food industry. Prescription of one of these categories of antibiotic may consequently select for bacteria resistant to both categories. Genetic mechanisms of resistance may be secondary to a chromosomal mutation located in quinolone resistance determining region of DNA gyrase or topoisomerase IV or to a plasmid acquisition. The insertion sequence ISCR1 is often associated with qnr and may favour its dissemination in Gram-negative bacteria. The aim of this study was to determine the genetic mechanism of quinolone resistance among extended-spectrum beta-lactamase-producing Enterobacteriaceae strains in the Central African Republic. Findings Among seventeen ESBL-producing Enterobacteriaceae isolated from urine, pus or stool between January 2003 and October 2005 in the Central African Republic, nine were resistant to ciprofloxacin (seven from community patients and two from hospitalized patients. The ESBL were previously characterized as CTX-M-15 and SHV-12. Susceptibility to nalidixic acid, norfloxacin and ciprofloxacin, and the minimal inhibitory concentrations of these drugs were determined by disc diffusion and agar dilution methods, respectively. The presence of plasmid-borne ISCR1-qnrA region was determined by PCR and amplicons, if any, were sent for sequencing. Quinolone resistance determining region of DNA gyrase gyrA gene was amplified by PCR and then sequenced for mutation characterization. We found that all CTX-M-producing strains were resistant to the tested quinolones. All the isolates had the same nucleotide mutation at codon 83 of gyrA. Two Escherichia coli strains with the highest MICs were shown to harbour an ISCR1-qnrA1 sequence. This genetic association might favour dissemination of resistance to quinolone and perhaps other antibiotics among Enterobacteriaceae

  10. Why Anticancer Nanomedicine Needs Sugars?

    Science.gov (United States)

    Bouffard, E; El Cheikh, K; Gallud, A; Da Silva, A; Maynadier, M; Basile, I; Gary-Bobo, M; Morere, A; Garcia, M

    2015-01-01

    Nowadays, nanomedicine brings new opportunities for diagnosis and treatment through innovative combinations of materials structured at the nanoscale, biomolecules and physicochemical processes. If the intrinsic properties of nanomaterials appear of major importance in this new discipline, the functionalization of these nanotools with biomolecules improves both their biocompatibility and efficacy. This is the case of carbohydrate derivatives, natural or synthetic, which are increasingly being used in nanostructures for medical purposes. As in current medicine, sugars are used to mimic their physiological roles. Indeed, carbohydrates enhance the solubility and reduce the clearance of drugs. They are used to mask immunogenic components of nano-objects and escape the body defenses and finally facilitate the delivery to the target tissue. All these properties explain the growing importance of sugars in nanomedicine.

  11. Molecular mechanisms of anti-cancer action of garlic compounds in neuroblastoma.

    Science.gov (United States)

    Karmakar, Surajit; Choudhury, Subhasree Roy; Banik, Naren L; Ray, Swapan K

    2011-05-01

    The medicinal properties of garlic (Allium sativum) have been well known and widely used since historical times. Garlic compounds have received increasing attention during the last few years due to their cancer chemopreventive properties. The anti-cancer activity of garlic-derived organosulfur compounds (OSCs) are extensively reported in many cancers but only a few in the pediatric tumor neuroblastoma, which warrants exploration of new therapy for its management. There are some recent reports suggesting that garlic-derived OSCs cause cell cycle arrest, generate reactive oxygen species (ROS), activate stress kinases, and also stimulate the mitochondrial pathway for apoptosis in malignant neuroblastoma. The comprehensive mechanisms of anti-cancer action of OSCs still remain unclear and require more studies in neuroblastoma. This review is designed to highlight the molecular mechanisms of anti-cancer actions of garlic-derived OSCs in neuroblastoma and as well as in several other cancers. Further studies should be conducted to establish the clinical expediency of garlic-derived OSCs for treatment of malignant neuroblastoma in humans.

  12. Superior anticancer activity of halogenated chalcones and flavonols over the natural flavonol quercetin.

    Science.gov (United States)

    Dias, Tatiana A; Duarte, Cecília L; Lima, Cristovao F; Proença, M Fernanda; Pereira-Wilson, Cristina

    2013-07-01

    A series of chalcone and flavonol derivatives were synthesized in good yield by an eco-friendly approach. A pharmacological evaluation was performed with the human colorectal carcinoma cell line HCT116 and revealed that the anticancer activity of flavonols was higher when compared with that of the respective chalcone precursors. The antiproliferative activity of halogenated derivatives increases as the substituent in the 3- or 4-positon of the B-ring goes from F to Cl and to Br. In addition, halogens in position 3 enhance anticancer activity in chalcones whereas for flavonol derivatives the best performance was registered for the 4-substituted derivatives. Flow cytometry analysis showed that compounds 3p and 4o induced cell cycle arrest and apoptosis as demonstrated by increased S, G2/M and sub-G1 phases. These data were corroborated by western blot and fluorescence microscopy analysis. In summary, halogenated chalcones and flavonols were successfully prepared and presented high anticancer activity as shown by their cell growth and cell cycle inhibitory potential against HCT116 cells, superior to that of quercetin, used as a positive control.

  13. Plant phytochemicals: potential anticancer agents against gastric cancer.

    Science.gov (United States)

    Øverby, Anders; Zhao, Chun-Mei; Chen, Duan

    2014-12-01

    Isothiocyanates (ITCs) are plant phytochemicals derived from vegetables consumed by human. ITCs comprise potent anti-carcinogenic agents of which the consumption has been linked to a reduced risk of cancer at several locations in the body. However, the studies on coping with gastric cancer remain unsatisfied. In the present review, ITCs are discussed in this context as ITCs may target gastric tumorigenesis at multiple levels. ITCs are taken up in the stomach, exposing mucosal and muscle layer cells as well as affecting Helicobacter pylori residing in the stomach. The natural and potent anti-cancer ITCs from vegetables have a great potential against gastric cancer, a disease in need of new treatment or preventive modalities.

  14. Engineering biosynthesis of the anticancer alkaloid noscapine in yeast.

    Science.gov (United States)

    Li, Yanran; Smolke, Christina D

    2016-07-05

    Noscapine is a potential anticancer drug isolated from the opium poppy Papaver somniferum, and genes encoding enzymes responsible for the synthesis of noscapine have been recently discovered to be clustered on the genome of P. somniferum. Here, we reconstitute the noscapine gene cluster in Saccharomyces cerevisiae to achieve the microbial production of noscapine and related pathway intermediates, complementing and extending previous in planta and in vitro investigations. Our work provides structural validation of the secoberberine intermediates and the description of the narcotoline-4'-O-methyltransferase, suggesting this activity is catalysed by a unique heterodimer. We also reconstitute a 14-step biosynthetic pathway of noscapine from the simple alkaloid norlaudanosoline by engineering a yeast strain expressing 16 heterologous plant enzymes, achieving reconstitution of a complex plant pathway in a microbial host. Other engineered yeasts produce previously inaccessible pathway intermediates and a novel derivative, thereby advancing protoberberine and noscapine related drug discovery.

  15. Engineering biosynthesis of the anticancer alkaloid noscapine in yeast

    Science.gov (United States)

    Li, Yanran; Smolke, Christina D.

    2016-01-01

    Noscapine is a potential anticancer drug isolated from the opium poppy Papaver somniferum, and genes encoding enzymes responsible for the synthesis of noscapine have been recently discovered to be clustered on the genome of P. somniferum. Here, we reconstitute the noscapine gene cluster in Saccharomyces cerevisiae to achieve the microbial production of noscapine and related pathway intermediates, complementing and extending previous in planta and in vitro investigations. Our work provides structural validation of the secoberberine intermediates and the description of the narcotoline-4′-O-methyltransferase, suggesting this activity is catalysed by a unique heterodimer. We also reconstitute a 14-step biosynthetic pathway of noscapine from the simple alkaloid norlaudanosoline by engineering a yeast strain expressing 16 heterologous plant enzymes, achieving reconstitution of a complex plant pathway in a microbial host. Other engineered yeasts produce previously inaccessible pathway intermediates and a novel derivative, thereby advancing protoberberine and noscapine related drug discovery. PMID:27378283

  16. Anticancer activity of botanical compounds in ancient fermented beverages (review).

    Science.gov (United States)

    McGovern, P E; Christofidou-Solomidou, M; Wang, W; Dukes, F; Davidson, T; El-Deiry, W S

    2010-07-01

    Humans around the globe probably discovered natural remedies against disease and cancer by trial and error over the millennia. Biomolecular archaeological analyses of ancient organics, especially plants dissolved or decocted as fermented beverages, have begun to reveal the preliterate histories of traditional pharmacopeias, which often date back thousands of years earlier than ancient textual, ethnohistorical, and ethnological evidence. In this new approach to drug discovery, two case studies from ancient Egypt and China illustrate how ancient medicines can be reconstructed from chemical and archaeological data and their active compounds delimited for testing their anticancer and other medicinal effects. Specifically, isoscopoletin from Artemisia argyi, artemisinin from Artemisia annua, and the latter's more easily assimilated semi-synthetic derivative, artesunate, showed the greatest activity in vitro against lung and colon cancers. In vivo tests of these compounds previously unscreened against lung and pancreatic cancers are planned for the future.

  17. A function of SmeDEF, the major quinolone resistance determinant of Stenotrophomonas maltophilia, is the colonization of plant roots.

    Science.gov (United States)

    García-León, Guillermo; Hernández, Alvaro; Hernando-Amado, Sara; Alavi, Peyman; Berg, Gabriele; Martínez, José Luis

    2014-08-01

    Quinolones are synthetic antibiotics, and the main cause of resistance to these antimicrobials is mutation of the genes encoding their targets. However, in contrast to the case for other organisms, such mutations have not been found in quinolone-resistant Stenotrophomonas maltophilia isolates, in which overproduction of the SmeDEF efflux pump is a major cause of quinolone resistance. SmeDEF is chromosomally encoded and highly conserved in all studied S. maltophilia strains; it is an ancient element that evolved over millions of years in this species. It thus seems unlikely that its main function would be resistance to quinolones, a family of synthetic antibiotics not present in natural environments until the last few decades. Expression of SmeDEF is tightly controlled by the transcriptional repressor SmeT. Our work shows that plant-produced flavonoids can bind to SmeT, releasing it from smeDEF and smeT operators. Antibiotics extruded by SmeDEF do not impede the binding of SmeT to DNA. The fact that plant-produced flavonoids specifically induce smeDEF expression indicates that they are bona fide effectors regulating expression of this resistance determinant. Expression of efflux pumps is usually downregulated unless their activity is needed. Since smeDEF expression is triggered by plant-produced flavonoids, we reasoned that this efflux pump may have a role in the colonization of plants by S. maltophilia. Our results showed that, indeed, deletion of smeE impairs S. maltophilia colonization of plant roots. Altogether, our results indicate that quinolone resistance is a recent function of SmeDEF and that colonization of plant roots is likely one original function of this efflux pump.

  18. Monte Carlo simulation for evaluation of the efficacy of carbapenems and new quinolones against ESBL-producing Escherichia coli.

    Science.gov (United States)

    Nakamura, Tatsuya; Shimizu, Chihiro; Kasahara, Mayumi; Okuda, Kazuyuki; Nakata, Chiyo; Fujimoto, Hiroko; Okura, Hiroe; Komatsu, Masaru; Shimakawa, Kouichi; Sueyoshi, Noriyuki; Ura, Toshiro; Satoh, Kaori; Toyokawa, Masahiro; Wada, Yasunao; Orita, Tamaki; Kofuku, Tomomi; Yamasaki, Katsutoshi; Sakamoto, Masako; Nishio, Hisaaki; Kinoshita, Shohiro; Takahashi, Hakuo

    2009-02-01

    Extended-spectrum beta-lactamase (ESBL)-producing bacteria are known to be resistant to penicillins, cephalosporins, and monobactams because of their substrate specificity, and these bacteria are sensitive only to a narrow range of antimicrobial agents. The present study was undertaken to evaluate the efficacy of carbapenems and the new quinolones against ESBL-producing Escherichia coli, using a Monte Carlo simulation based on the pharmacokinetic/pharmacodynamic (PK/PD) theory. The time above MIC (TAM, %) served as the PK/PD parameter for carbapenems, with the target level set at 40%. The AUC/MIC served as the PK/PD parameter for the new quinolones, with the target level set at more than 125. In the analysis of drug sensitivity, the MIC50 of all carbapenems other than imipenem was low (0.03 microg/ml), while the MIC50 of the new quinolones was higher (1-2 microg/ml). The probability of achieving the PK/PD target with carba penems after two doses at the usual dose level, as determined by the Monte Carlo simulation, was high for each of the carbapenems tested (99.0% for biapenem, 99.60% for meropenem, and 95.03% for doripenem), except for imipenem. Among the new quinolones, the highest probability of achieving the PK/PD target was obtained with pazufloxacin (42.90%). Thus, the results of the present study have revealed that carbapenems are effective at the regular dose and can be used as the first-choice antibiotics for ESBL-producing E. coli because the resistance ratios for carbapenems are low compared to those of the new quinolones.

  19. Teratogens as anti-cancer drugs.

    Science.gov (United States)

    Blagosklonny, Mikhail V

    2005-11-01

    Most anticancer drugs are teratogens, merely because they target vital cellular functions. Conversely, some plants produce agents that intentionally target embryonic signaling pathways, precisely to cause birth defects if pregnant animals eat such plants. Cyclopamine, a teratogen produced by a flowering plant, inhibits the Hh/Gli pathway, causing developmental defects such as cyclopia (one eye in the middle of the face). In theory, selective teratogens may suppress cancer cells that reactivate embryonic pathways, while sparing most normal cells. I discuss the potential (and limits) of teratogens in cancer therapy, linking diverse topics from morning sickness of pregnancy, embryonic pathways and poisonous plants to the mechanism of action of anticancer teratogens and their combinations with less selective cytotoxic agents.

  20. Are isothiocyanates potential anti-cancer drugs?

    Institute of Scientific and Technical Information of China (English)

    Xiang WU; Qing-hua ZHOU; Ke XU

    2009-01-01

    Isothiocyanates are naturally occurring small molecules that are formed from glucosinolate precursors of cruciferous vegetables. Many isothiocyanates, both natural and synthetic, display anticarcinogenic activity because they reduce activation of carcinogens and increase their detoxification. Recent studies show that they exhibit anti-tumor activity by affecting multiple pathways including apoptosis, MAPK signaling, oxidative stress, and cell cycle progression. This review summarizes the current knowledge on isothiocyanates and focuses on their role as potential anti-cancer agents.

  1. Anticancer Properties of Phyllanthus emblica (Indian Gooseberry)

    OpenAIRE

    Tiejun Zhao; Qiang Sun; Maud Marques; Michael Witcher

    2015-01-01

    There is a wealth of information emanating from both in vitro and in vivo studies indicating fruit extract of the Phyllanthus emblica tree, commonly referred to as Indian Gooseberries, has potent anticancer properties. The bioactivity in this extract is thought to be principally mediated by polyphenols, especially tannins and flavonoids. It remains unclear how polyphenols from Phyllanthus emblica can incorporate both cancer-preventative and antitumor properties. The antioxidant function of Ph...

  2. Recent Development of Anticancer Therapeutics Targeting Akt

    OpenAIRE

    Morrow, John K.; Du-Cuny, Lei; Chen, Lu; Meuillet, Emmanuelle J.; Eugene A Mash; Powis, Garth; Zhang, Shuxing

    2011-01-01

    The serine/threonine kinase Akt has proven to be a significant signaling target, involved in various biological functions. Because of its cardinal role in numerous cellular responses, Akt has been implicated in many human diseases, particularly cancer. It has been established that Akt is a viable and feasible target for anticancer therapeutics. Analysis of all Akt kinases reveals conserved homology for an N-terminal regulatory domain, which contains a pleckstrin-homology (PH) domain for cellu...

  3. [Quod medicina aliis, aliis est acre venenum**--venoms as a source of anticancer agents].

    Science.gov (United States)

    Kucińska, Małgorzata; Ruciński, Piotr; Murias, Marek

    2013-01-01

    Natural product derived from plants and animals were used in folk medicine for centuries. The venoms produced by animals for hunting of self-defence are rich in bioactive compounds with broad spectrum of biological activity. The papers presents the most promising compounds isolated from venoms of snakes, scorpions and toads. For these compounds both: mechanism of anticancer activity as well as possibilities of clinical use are presented.

  4. Peroxisome Proliferator Activated Receptor A Ligands as Anticancer Drugs Targeting Mitochondrial Metabolism

    OpenAIRE

    Grabacka, Maja; Pierzchalska, Malgorzata; Reiss, Krzysztof

    2013-01-01

    Tumor cells show metabolic features distinctive from normal tissues, with characteristically enhanced aerobic glycolysis, glutaminolysis and lipid synthesis. Peroxisome proliferator activated receptor α (PPAR α) is activated by nutrients (fatty acids and their derivatives) and influences these metabolic pathways acting antagonistically to oncogenic Akt and c-Myc. Therefore PPAR α can be regarded as a candidate target molecule in supplementary anticancer pharmacotherapy as well as dietary ther...

  5. The Role of Endophytic Fungi in the Anticancer Activity of Morinda citrifolia Linn. (Noni)

    OpenAIRE

    Yougen Wu; Sisay Girmay; Vitor Martins da Silva; Brian Perry; Xinwen Hu; Tan, Ghee T.

    2015-01-01

    We hypothesize that the fungal endophytes of noni may possibly play a role in its overall pharmacological repertoire, especially since the perceived efficacy of the fruit in ethnomedicinal use is associated with the fermented juice. The foremost goal of this study is to explore the role of endophyte-derived secondary metabolites in the purported anticancer properties of noni. To that end, culturable endophytic fungi resident within the healthy leaves and fruit of the plant were isolated and i...

  6. Synthesis and anticancer activity of (+-nopinone-based 2-amino-3-cyanopyridines

    Directory of Open Access Journals (Sweden)

    Shengliang LIAO,Shibin SHANG,Minggui SHEN,Xiaoping RAO,Hongyan SI,Jie SONG,Zhanqian SONG

    2015-12-01

    Full Text Available Twelve (+-nopinone-based 2-amino-3-cyanopyridines 4a—l were synthesized from (—-β-pinene. The structures of these compounds were characterized by FT-IR, 1H NMR, and ESI-MS. All the compounds were tested for their anticancer activity against lung cancer cell line A549, gastric cancer cell line MKN45 and breast cancer cell line MCF7 by MTT method, respectively. The results showed that compounds 4f, 4j and 4k had promising anticancer activity against these cancer cell lines, in particular, compound 4f exhibited broad-spectrum and highly efficient anticancer activity against cell lines A549, MKN45 and MCF7 with IC50 of 23.78, 67.61 and 53.87 μmol·L-1, respectively. The preliminary analysis of the structure activity relationship implied that the Br or Cl substituted group of the benzene ring in these derivatives significantly contributed to the anticancer activity.

  7. Resistance patterns to beta-lactams and quinolones in clinical isolates of bacteria from Cuban hospitals.

    Science.gov (United States)

    Gonzáles, I; Niebla, A; Vallin, C

    1995-01-01

    The resistance patterns to 26 beta-lactams and 8 quinolones of clinical isolates from Cuban hospitals were evaluated using the disk susceptibility test, according to the NCCLS guidelines (1992). The genera studied were Escherichia sp (320), Enterobacter sp (10), Klebsiella sp (90), Proteus sp (10), Pseudomonas sp (90), Serratia sp (20), and Staphylococcus sp (80). Higher resistance to beta-lactams was observed in the genera Pseudomonas, Escherichia and Klebsiella. For fluoroquinolones we found no significant resistance, with the exception of the genus Klebsiella. The most effective antibiotics were cephalosporins of the second and third generations, fluoroquinolones, and non-classical beta-lactams (cephamycins, moxalactam and monobactams). On the contrary, a pronounced resistance was found to penicillin, oxacillin, ticarcillin, ampicillin, methicillin, nalidixic acid and cinoxacin. These resistance patterns correspond to the high consumption of these antibiotics throughout the country.

  8. C-6 aryl substituted 4-quinolone-3-carboxylic acids as inhibitors of hepatitis C virus.

    Science.gov (United States)

    Chen, Yue-Lei; Zacharias, Jeana; Vince, Robert; Geraghty, Robert J; Wang, Zhengqiang

    2012-08-01

    Quinolone-3-carboxylic acid represents a highly privileged chemotype in medicinal chemistry and has been extensively explored as antibiotics and antivirals targeting human immunodeficiency virus (HIV) integrase (IN). Herein we describe the synthesis and anti-hepatitis C virus (HCV) profile of a series of C-6 aryl substituted 4-quinlone-3-carboxylic acid analogues. Significant inhibition was observed with a few analogues at low micromolar range against HCV replicon in cell culture and a reduction in replicon RNA was confirmed through an RT-qPCR assay. Interestingly, evaluation of analogues as inhibitors of NS5B in a biochemical assay yielded only modest inhibitory activities, suggesting that a different mechanism of action could operate in cell culture.

  9. Capillary electrophoresis with electrochemiluminescence detection for the analysis of quinolone drugs and pharmacokinetics study

    Institute of Scientific and Technical Information of China (English)

    Yan Ming Liu; Jun Tao Cao; Hui Wang

    2008-01-01

    A novel method for the determination of two quinolone drugs norfloxacin (NOR) and levofloxacin (LVX) was described by capillary electrophoresis with electrochemiluminescence detection. The good relationship (r ≥ 0.9991) between peak area and concentration of analytes was established over two orders of magnitude. The limits of detection (LOD, S/N = 3) in standard solution are 4.8 × 10-7 mol/L for NOR and 6.4 × 10-7 mol/L for LVX, respectively. The limits of quantitation (LOQ, S/N = 10) in real human urine samples are 1.2 × 10-6 mol/L for NOR and 1.4 × 10-6 mol/L for LVX, respectively. The present method was successfully applied to the determination of NOR and LVX in human urine and the study of pharmacokinetics of NOR.

  10. Advances in cobalt complexes as anticancer agents.

    Science.gov (United States)

    Munteanu, Catherine R; Suntharalingam, Kogularamanan

    2015-08-21

    The evolution of resistance to traditional platinum-based anticancer drugs has compelled researchers to investigate the cytostatic properties of alternative transition metal-based compounds. The anticancer potential of cobalt complexes has been extensively studied over the last three decades, and much time has been devoted to understanding their mechanisms of action. This perspective catalogues the development of antiproliferative cobalt complexes, and provides an in depth analysis of their mode of action. Early studies on simple cobalt coordination complexes, Schiff base complexes, and cobalt-carbonyl clusters will be documented. The physiologically relevant redox properties of cobalt will be highlighted and the role this plays in the preparation of hypoxia selective prodrugs and imaging agents will be discussed. The use of cobalt-containing cobalamin as a cancer specific delivery agent for cytotoxins will also be described. The work summarised in this perspective shows that the biochemical and biophysical properties of cobalt-containing compounds can be fine-tuned to produce new generations of anticancer agents with clinically relevant efficacies.

  11. Anticancer Drugs from Marine Flora: An Overview

    Directory of Open Access Journals (Sweden)

    N. Sithranga Boopathy

    2010-01-01

    Full Text Available Marine floras, such as bacteria, actinobacteria, cyanobacteria, fungi, microalgae, seaweeds, mangroves, and other halophytes are extremely important oceanic resources, constituting over 90% of the oceanic biomass. They are taxonomically diverse, largely productive, biologically active, and chemically unique offering a great scope for discovery of new anticancer drugs. The marine floras are rich in medicinally potent chemicals predominantly belonging to polyphenols and sulphated polysaccharides. The chemicals have displayed an array of pharmacological properties especially antioxidant, immunostimulatory, and antitumour activities. The phytochemicals possibly activate macrophages, induce apoptosis, and prevent oxidative damage of DNA, thereby controlling carcinogenesis. In spite of vast resources enriched with chemicals, the marine floras are largely unexplored for anticancer lead compounds. Hence, this paper reviews the works so far conducted on this aspect with a view to provide a baseline information for promoting the marine flora-based anticancer research in the present context of increasing cancer incidence, deprived of the cheaper, safer, and potent medicines to challenge the dreadful human disease.

  12. Prevalence of Plasmid-Mediated Quinolone Resistance Genes among Ciprofloxacin-Nonsusceptible Escherichia coli and Klebsiella pneumoniae Isolated from Blood Cultures in Korea

    Directory of Open Access Journals (Sweden)

    Hee Young Yang

    2014-01-01

    Full Text Available OBJECTIVES:To analyze the prevalence of plasmid-mediated quinolone resistance (PMQR determinants in ciprofloxacin-nonsusceptible Escherichia coli and Klebsiella pneumoniae isolated from patients at a tertiary care hospital in Korea.

  13. Coexistence of blaOXA-23 with armA in quinolone-resistant Acinetobacter baumannii from a Chinese university hospital.

    Science.gov (United States)

    Shen, Min; Luan, Guangxin; Wang, Yanhong; Chang, Yaowen; Zhang, Chi; Yang, Jingni; Deng, Shanshan; Ling, Baodong; Jia, Xu

    2016-03-01

    A total of 101 Acinetobacter baumannii isolates were collected to determine the mechanisms of quinolone resistance and investigate the occurrence of carbapenem and high-level aminoglycoside resistance genes among quinolone-resistant strains. Among 77 quinolone-resistant A. baumannii harbored mutations of gyrA and parC, 41 isolates, which belonged to European clone II, had resistance to aminoglycosides and carbapenems due to the expression of armA and acquisition of blaOXA-23. Most of sequence type belonged to clonal complex 92. These results suggested hospital dissemination of multidrug-resistant A. baumannii carrying blaOXA-23, armA, and mutations of quinolone resistance-determining regions in western China.

  14. Plasmid-mediated quinolone resistance among extended spectrum beta lactase producing Enterobacteriaceae from bloodstream infections.

    Science.gov (United States)

    Domokos, Judit; Kristóf, Katalin; Szabó, Dóra

    2016-09-01

    The purpose of this study was to determine prevalence and molecular characterization of plasmid-mediated quinolone resistance (PMQR) genes [qnrA, qnrB, qnrC, qnrD, qnrS, aac(6')-Ib-cr, qepA, and oqxAB] among extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella spp. isolates from bloodcultures in Hungary. A total of 103 isolates were tested for quinolone susceptibility by microdilution method and PMQR genes were detected by polymerase chain reaction. About 40 ESBL-producing E. coli (39%) and 50 ESBL-producing Klebsiella spp. strains (48%) were resistant to ciprofloxacin; 40 ESBL-producing E. coli (39%) and 47 ESBL-producing Klebsiella spp. strains (45%) were resistant to levofloxacin; and 88 strains including 40 ESBL-producing E. coli (39%) and 48 (47%) ESBL-producing Klebsiella spp. were resistant to moxifloxacin. Among the 103 ESBL-producing isolates, 77 (75%) isolates (30 E. coli and 47 Klebsiella spp.) harbored PMQR genes. The most commonly detected gene was aac(6')-Ib-cr (65%). The occurrence of qnrS gene was 6%. Interestingly, qnrA, qnrB, qnrC, qnrD, and qepA were not found in any isolates. Among 77 PMQR-positive isolates, 27 (35.1%) and 1 (1.3%) carried two and three different PMQR genes, respectively. Only Klebsiella spp. harbored more than one PMQR genes. Observing prevalence of PMQR genes in the last 8 years, the increasing incidence of aac(6')-Ib-cr and oqxAB can be seen. Our results highlight high frequency of PMQR genes among ESBL-producing Klebsiella pneumoniae and E. coli isolates with an increasing dynamics in Hungary.

  15. QUINOLONE- AND ETA-LACTAM- RESISTANCE IN Escherichia coli FROM DANISH AND ITALIAN BROILER FLOCKS

    Directory of Open Access Journals (Sweden)

    M. Trevisani

    2009-03-01

    Full Text Available The prevalence of quinolone- and -lactam-resistant E. coli was investigated among healthy broiler flocks in Denmark and Italy. In Denmark, sock samples were collected from 10 parent flocks and 10 offspring flocks, according to the procedure currently used for the surveillance of Salmonella in the EU. Samples were enriched in McConkey broth and streaked on McConkey agar plates added with nalidixic acid (32 g/ml, ciprofloxacin (2 g/ml, ampicillin (32 g/ml, cefotaxime (2 g/ml or ceftiofur (8 g/ml. The -glucuronidase test was performed for verification of presumptive E. coli. The same methods were used to analyse sock samples collected from 6 Italian broiler flocks. PCR with primers for the CTX-M-type extended-spectrum -lactamases (ESBLs was performed on cephalosporin-resistant isolates. While resistance to ampicillin and nalidixic acid was widespread in both countries, resistance to ciprofloxacin and cephalosporins was more common among Italian flocks. In Denmark, ciprofloxacin resistance was only detected in 1 parent flock without any history of quinolone usage and none of the flocks was positive for cephalosporin-resistant E. coli. In Italy, resistance to ciprofloxacin was detected in all flocks and resistance to ceftiofur and cefotaxime were detected in 5 flocks. Primers specific for the CTX-M-type ESBLs generated PCR amplicons from isolates from 3 of these flocks. In industrialized countries, the poultry production system is highly standardized, and therefore comparable. However, the use of broad-spectrum antimicrobials is particularly limited in Danish poultry production. Accordingly, the results of this study could reflect the different policies in antimicrobial usage between the two countries.

  16. Characterization of antimicrobial resistance in Salmonella enterica food and animal isolates from Colombia: identification of a qnrB19-mediated quinolone resistance marker in two novel serovars

    DEFF Research Database (Denmark)

    Karczmarczyk, M.; Martins, M.; McCusker, M.

    2010-01-01

    Ninety-three Salmonella isolates recovered from commercial foods and exotic animals in Colombia were studied. The serotypes, resistance profiles and where applicable the quinolone resistance genes were determined. Salmonella Anatum (n=14), Uganda (19), Braenderup (10) and Newport (10) were the most...... hitherto unrecognized in various Salmonella serovars in Colombia. We also report unusual high-level quinolone resistance in the absence of any DNA gyrase mutations in serovars S. Carrau, Muenchen and Uganda....

  17. Influence of the π-coordinated arene on the anticancer activity of ruthenium(II) carbohydrate organometallic complexes

    NARCIS (Netherlands)

    Hanif, Muhammad; Meier, Samuel M; Nazarov, Alexey A; Risse, Julie; Legin, Anton; Casini, Angela; Jakupec, Michael A; Keppler, Bernhard K; Hartinger, Christian G

    2013-01-01

    The synthesis and in vitro cytotoxicity of a series of Ru(II)(arene) complexes with carbohydrate-derived phosphite ligands and various arene co-ligands is described. The arene ligand has a strong influence on the in vitro anticancer activity of this series of compounds, which correlates fairly well

  18. Anticancer Efficacy of Polyphenols and Their Combinations

    Directory of Open Access Journals (Sweden)

    Aleksandra Niedzwiecki

    2016-09-01

    Full Text Available Polyphenols, found abundantly in plants, display many anticarcinogenic properties including their inhibitory effects on cancer cell proliferation, tumor growth, angiogenesis, metastasis, and inflammation as well as inducing apoptosis. In addition, they can modulate immune system response and protect normal cells against free radicals damage. Most investigations on anticancer mechanisms of polyphenols were conducted with individual compounds. However, several studies, including ours, have indicated that anti-cancer efficacy and scope of action can be further enhanced by combining them synergistically with chemically similar or different compounds. While most studies investigated the anti-cancer effects of combinations of two or three compounds, we used more comprehensive mixtures of specific polyphenols and mixtures of polyphenols with vitamins, amino acids and other micronutrients. The mixture containing quercetin, curcumin, green tea, cruciferex, and resveratrol (PB demonstrated significant inhibition of the growth of Fanconi anemia head and neck squamous cell carcinoma and dose-dependent inhibition of cell proliferation, matrix metalloproteinase (MMP-2 and -9 secretion, cell migration and invasion through Matrigel. PB was found effective in inhibition of fibrosarcoma HT-1080 and melanoma A2058 cell proliferation, MMP-2 and -9 expression, invasion through Matrigel and inducing apoptosis, important parameters for cancer prevention. A combination of polyphenols (quercetin and green tea extract with vitamin C, amino acids and other micronutrients (EPQ demonstrated significant suppression of ovarian cancer ES-2 xenograft tumor growth and suppression of ovarian tumor growth and lung metastasis from IP injection of ovarian cancer A-2780 cells. The EPQ mixture without quercetin (NM also has shown potent anticancer activity in vivo and in vitro in a few dozen cancer cell lines by inhibiting tumor growth and metastasis, MMP-2 and -9 secretion, invasion

  19. Characterization of HmqF, a protein involved in the biosynthesis of unsaturated quinolones produced by Burkholderia thailandensis.

    Science.gov (United States)

    Agarwal, Aparna; Kahyaoglu, Caroline; Hansen, Darren B

    2012-02-28

    The opportunistic pathogen Burkholderia thailandensis produces a number of structurally similar unsaturated quinolones involved in quorum sensing. However, little is known about the biosynthesis of these unsaturated quinolones. In this study, we have characterized the starting point of the biosynthesis of unsaturated quinolone molecules produced in B. thailandensis. We have shown by using in vitro enzymology, liquid chromatography, and mass spectrometry that protein HmqF is involved in the biosynthesis of unsaturated quinolones produced by B. thailandensis. HmqF consists of three domains: an adenylation domain (A domain), a dehydrogenase domain (DH domain), and an acyl carrier domain (ACP). The three domains (A, DH, and ACP) were cloned and expressed individually in Escherichia coli, and their reactivity was studied using high-performance liquid chromatography (HPLC) and mass spectrometry (MS) based assays. Our in vitro studies show that the A domain catalyzes ATP-dependent activation of medium chain (C6-C14) fatty acids without activation by coenzyme A (CoA). Results from competition assays are consistent with decanoic acid being the preferred substrate. Incubation of the ACP domain with 4'-phosphopantetheine transferase and CoA led to the formation of phosphopantetheinylated ACP (Ppant-ACP). In a Ppant ejection assay using tandem MS (MS/MS), a mass consistent with the mass of a cyclic variant of dephosphorylated Ppant was detected. We further demonstrated that Ppant-ACP could be loaded with medium chain fatty acids in the presence of ATP and the A domain. MS analysis was consistent with the formation of Ppant-ACP thiol esters of the fatty acids. MS/MS Ppant ejection experiments confirmed the loss of 2H in samples of fatty acid-loaded Ppant-ACP in the presence of the DH domain. HPLC analysis of benzyl amide ligation products allowed us to conclude that dehydrogenation produced trans-β,γ-unsaturation in the fatty acid chains. Our results are in good agreement

  20. 金属离子对喹诺酮活性影响的研究进展%Research Progress of Metal Ions Influence The Activity of Quinolone

    Institute of Scientific and Technical Information of China (English)

    范卓文; 朱丽华; 杨爽爽; 闫丽莉; 孙建华

    2014-01-01

    喹诺酮类药物以抗菌活性强、抗菌谱广、疗效确切等优点被广泛应用于临床,一些研究结果表明金属离子对喹诺酮类药物的活性有一定的影响。本文概述了喹诺酮类药物的发展及作用机制,总结了金属离子对喹诺酮类的作用及喹诺酮类药物金属配合物的活性,最后展望了喹诺酮类药物今后的发展。%Quinolone are widely used clinically because of its antibacterial activity, widely spectrum antimicrobial, curative ef-fect, etc.Some studies show that the metal ions affect the activity of quinolone.This paper outlines the development and action mecha-nism of quinolone. Summarizes the role of metal ions on metal quinolone and the biological activity of quinolone complexes. Finally, prospects of the development of quinolone.

  1. Alarmingly High Segregation Frequencies of Quinolone Resistance Alleles within Human and Animal Microbiomes Are Not Explained by Direct Clinical Antibiotic Exposure.

    Science.gov (United States)

    Field, Wesley; Hershberg, Ruth

    2015-05-26

    Antibiotic resistance poses a major threat to human health. It is therefore important to characterize the frequency of resistance within natural bacterial environments. Many studies have focused on characterizing the frequencies with which horizontally acquired resistance genes segregate within natural bacterial populations. Yet, very little is currently understood regarding the frequency of segregation of resistance alleles occurring within the housekeeping targets of antibiotics. We surveyed a large number of metagenomic datasets extracted from a large variety of host-associated and non host-associated environments for such alleles conferring resistance to three groups of broad spectrum antibiotics: streptomycin, rifamycins, and quinolones. We find notable segregation frequencies of resistance alleles occurring within the target genes of each of the three antibiotics, with quinolone resistance alleles being the most frequent and rifamycin resistance alleles being the least frequent. Resistance allele frequencies varied greatly between different phyla and as a function of environment. The frequency of quinolone resistance alleles was especially high within host-associated environments, where it averaged an alarming ∼ 40%. Within host-associated environments, resistance to quinolones was most often conferred by a specific resistance allele. High frequencies of quinolone resistance alleles were also found within hosts that were not directly treated with antibiotics. Therefore, the high segregation frequency of quinolone resistance alleles occurring within the housekeeping targets of antibiotics in host-associated environments does not seem to be the sole result of clinical antibiotic usage.

  2. Endochin optimization: structure-activity and structure-property relationship studies of 3-substituted 2-methyl-4(1H)-quinolones with antimalarial activity.

    Science.gov (United States)

    Cross, R Matthew; Monastyrskyi, Andrii; Mutka, Tina S; Burrows, Jeremy N; Kyle, Dennis E; Manetsch, Roman

    2010-10-14

    Since the 1940s endochin and analogues thereof were known to be causal prophylactic and potent erythrocytic stage agents in avian models. Preliminary screening in a current in vitro assay identified several 4(1H)-quinolones with nanomolar EC(50) against erythrocytic stages of multidrug resistant W2 and TM90-C2B isolates of Plasmodium falciparum. Follow-up structure-activity relationship (SAR) studies on 4(1H)-quinolone analogues identified several key features for biological activity. Nevertheless, structure-property relationship (SPR) studies conducted in parallel revealed that 4(1H)-quinolone analogues are limited by poor solubilities and rapid microsomal degradations. To improve the overall efficacy, multiple 4(1H)-quinolone series with varying substituents on the benzenoid quinolone ring and/or the 3-position were synthesized and tested for in vitro antimalarial activity. Several structurally diverse 6-chloro-2-methyl-7-methoxy-4(1H)-quinolones with EC(50) in the low nanomolar range against the clinically relevant isolates W2 and TM90-C2B were identified with improved physicochemical properties while maintaining little to no cross-resistance with atovaquone.

  3. A Systematic Review of Iran's Medicinal Plants With Anticancer Effects.

    Science.gov (United States)

    Asadi-Samani, Majid; Kooti, Wesam; Aslani, Elahe; Shirzad, Hedayatollah

    2016-04-01

    Increase in cases of various cancers has encouraged the researchers to discover novel, more effective drugs from plant sources. This study is a review of medicinal plants in Iran with already investigated anticancer effects on various cell lines. Thirty-six medicinal plants alongside their products with anticancer effects as well as the most important plant compounds responsible for the plants' anticancer effect were introduced. Phenolic and alkaloid compounds were demonstrated to have anticancer effects on various cancers in most studies. The plants and their active compounds exerted anticancer effects by removing free radicals and antioxidant effects, cell cycle arrest, induction of apoptosis, and inhibition of angiogenesis. The investigated plants in Iran contain the compounds that are able to contribute effectively to fighting cancer cells. Therefore, the extract and active compounds of the medicinal plants introduced in this review article could open a way to conduct clinical trials on cancer and greatly help researchers and pharmacists develop new anticancer drugs.

  4. Interactions of the "piano-stool" [ruthenium(II)(η(6) -arene)(quinolone)Cl](+) complexes with water; DFT computational study.

    Science.gov (United States)

    Zábojníková, Tereza; Cajzl, Radim; Kljun, Jakob; Chval, Zdeněk; Turel, Iztok; Burda, Jaroslav V

    2016-07-15

    Full optimizations of stationary points along the reaction coordinate for the hydration of several quinolone Ru(II) half-sandwich complexes were performed in water environment using the B3PW91/6-31+G(d)/PCM/UAKS method. The role of diffuse functions (especially on oxygen) was found crucial for correct geometries along the reaction coordinate. Single-point (SP) calculations were performed at the B3LYP/6-311++G(2df,2pd)/DPCM/saled-UAKS level. In the first part, two possible reaction mechanisms-associative and dissociative were compared. It was found that the dissociative mechanism of the hydration process is kinetically slightly preferred. Another important conclusion concerns the reaction channels. It was found that substitution of chloride ligand (abbreviated in the text as dechlorination reaction) represents energetically and kinetically the most feasible pathway. In the second part the same hydration reaction was explored for reactivity comparison of the Ru(II)-complexes with several derivatives of nalidixic acid: cinoxacin, ofloxacin, and (thio)nalidixic acid. The hydration process is about four orders of magnitude faster in a basic solution compared to neutral/acidic environment with cinoxacin and nalidixic acid as the most reactive complexes in the former and latter environments, respectively. The explored hydration reaction is in all cases endergonic; nevertheless the endergonicity is substantially lower (by ∼6 kcal/mol) in basic environment. © 2016 Wiley Periodicals, Inc.

  5. Anticancer drug sensitivity by human tumor clonogenic assay.

    Directory of Open Access Journals (Sweden)

    Hiraki,Shunkichi

    1986-10-01

    Full Text Available The anticancer drug sensitivity of human cancers was tested by the human tumor clonogenic assay (HTCA. Of 152 human cancer specimens tested, 63 (41% formed more than 30 tumor cell colonies in control plates and could be used to evaluate the drug sensitivity of tumor cells. In 42 (93% of 45 clinical trials in 24 patients, a parallel correlation was observed between the in vitro anticancer drug sensitivity measured by the HTCA and the clinical response of tumors to anticancer drugs. These results suggest that the HTCA is a good technique for the in vitro test of the anticancer drug sensitivity of human cancers.

  6. CancerHSP: anticancer herbs database of systems pharmacology

    Science.gov (United States)

    Tao, Weiyang; Li, Bohui; Gao, Shuo; Bai, Yaofei; Shar, Piar Ali; Zhang, Wenjuan; Guo, Zihu; Sun, Ke; Fu, Yingxue; Huang, Chao; Zheng, Chunli; Mu, Jiexin; Pei, Tianli; Wang, Yuan; Li, Yan; Wang, Yonghua

    2015-01-01

    The numerous natural products and their bioactivity potentially afford an extraordinary resource for new drug discovery and have been employed in cancer treatment. However, the underlying pharmacological mechanisms of most natural anticancer compounds remain elusive, which has become one of the major obstacles in developing novel effective anticancer agents. Here, to address these unmet needs, we developed an anticancer herbs database of systems pharmacology (CancerHSP), which records anticancer herbs related information through manual curation. Currently, CancerHSP contains 2439 anticancer herbal medicines with 3575 anticancer ingredients. For each ingredient, the molecular structure and nine key ADME parameters are provided. Moreover, we also provide the anticancer activities of these compounds based on 492 different cancer cell lines. Further, the protein targets of the compounds are predicted by state-of-art methods or collected from literatures. CancerHSP will help reveal the molecular mechanisms of natural anticancer products and accelerate anticancer drug development, especially facilitate future investigations on drug repositioning and drug discovery. CancerHSP is freely available on the web at http://lsp.nwsuaf.edu.cn/CancerHSP.php. PMID:26074488

  7. Luminescent determination of quinolones in milk samples by liquid chromatography/post-column derivatization with terbium oxide nanoparticles.

    Science.gov (United States)

    Yánez-Jácome, G S; Aguilar-Caballos, M P; Gómez-Hens, A

    2015-07-31

    The usefulness of terbium oxide nanoparticles (Tb4O7NPs) as post-column derivatizing reagent for the liquid chromatographic determination of residues of quinolone antibiotics in milk samples has been studied. Seven quinolones of veterinary use have been chosen as model analytes to develop this method. The derivatization step is based on the formation of luminescent chelates of quinolones with Tb4O7NPs, which are monitored at λex=340nm and λem=545nm. Another relevant feature of the method is that the use of a 10-cm column and a ternary mixture of methanol, acetonitrile and acetic acid as mobile phase in gradient elution mode allow the chromatographic separation of the quinolones in about 13min, whereas previously described chromatographic methods require about 20min. The dynamic ranges of the calibration graphs and limits of detection are, respectively: 65-900ngmL(-1) and 35ngmL(-1) for marbofloxacin, 7.2-900ngmL(-1) and 2.5ngmL(-1) for ciprofloxacin, 6-900ngmL(-1) and 2ngmL(-1) for danofloxacin, 50-900ngmL(-1) and 20ngmL(-1) for enrofloxacin, 35-900ngmL(-1) and 12ngmL(-1) for sarafloxacin, 5-900ngmL(-1) and 2ngmL(-1) for oxolinic acid, and 7-900ngmL(-1) and 2.5ngmL(-1) for flumequine. The precision, established at two concentration levels of each analyte and expressed as the percentage of the relative standard deviation is in the range of 1.9-8.1% using standards, and of 3.4-10.7% in the presence of milk samples. The method has been satisfactorily applied to the analysis of skimmed, semi-skimmed and whole milk samples, with recoveries ranging from 89.0 to 106.5%.

  8. Pharmacokinetics of Sparfloxacin in the Serum and Vitreous Humor of Rabbits: Physicochemical Properties That Regulate Penetration of Quinolone Antimicrobials

    Science.gov (United States)

    Liu, Weiguo; Liu, Qing Feng; Perkins, Ruth; Drusano, George; Louie, Arnold; Madu, Assumpta; Mian, Umar; Mayers, Martin; Miller, Michael H.

    1998-01-01

    We have used a recently described animal model to characterize the ocular pharmacokinetics of sparfloxacin in vitreous humor of uninfected albino rabbits following systemic administration and direct intraocular injection. The relationships of lipophilicity, protein binding, and molecular weight to the penetration and elimination of sparfloxacin were compared to those of ciprofloxacin, fleroxacin, and ofloxacin. To determine whether elimination was active, elimination rates following direct injection with and without probenecid or heat-killed bacteria were compared. Sparfloxacin concentrations were measured in the serum and vitreous humor by a biological assay. Protein binding and lipophilicity were determined, respectively, by ultrafiltration and oil-water partitioning. Pharmacokinetic parameters were characterized with RSTRIP, an iterative, nonlinear, weighted, least-squares-regression program. The relationship between each independent variable and mean quinolone concentration or elimination rate in the vitreous humor was determined by multiple linear regression. The mean concentration of sparfloxacin in the vitreous humor was 59.4% ± 12.2% of that in serum. Penetration of sparfloxacin, ciprofloxacin, fleroxacin, and ofloxacin into, and elimination from, the vitreous humor correlated with lipophilicity (r2 > 0.999). The linear-regression equation describing this relationship was not improved by including the inverse of the square root of the molecular weight and/or the degree of protein binding. Elimination rates for each quinolone were decreased by the intraocular administration of probenecid. Heat-killed Staphylococcus epidermidis decreased the rate of elimination of fleroxacin. Penetration of sparfloxacin into the noninflamed vitreous humor was greater than that of any quinolone previously examined. There was an excellent correlation between lipophilicity and vitreous entry or elimination for sparfloxacin as well as ciprofloxacin, fleroxacin, and ofloxacin

  9. Reactions and interactions in handling anticancer drugs.

    Science.gov (United States)

    D'Arcy, P F

    1983-01-01

    The clinical toxicity of anticancer drugs has been well documented with regard to the adverse effects of treatment in patients. However, many of these drugs have a direct irritant effect on the skin, eyes, mucous membranes, and other tissues. Handled without due care, especially when being prepared for injection, most cytotoxic drugs can cause local toxic or allergic reactions; they also present hazards of carcinogenicity and mutagenicity. This spectrum of potential risk should be kept in mind by personnel administering or handling these drugs, especially in oncology units where just a few individuals may routinely and frequently reconstitute many doses of cytotoxic agents. This is work in which the hospital pharmacist should and must be involved; indeed, many of the techniques and skills required are identical with those used in standard aseptic procedures for preparing pharmaceutical products. Pharmacy departments should take the initiative in making hospital staff aware of the potential risks of handling neoplastic agents, and they should spearhead a multidisciplinary assessment for producing local guidelines for working with these drugs. This article warns practitioners about the inherent dangers of these practitioner-drug interactions and suggests ways in which they may be reduced. Information is given in tabular form regarding recommended procedures for reconstituting 24 anticancer drugs and precautions to protect the personnel handling them, especially when there is spillage of powdered or liquid drugs. Also, guidelines are given about incompatibilities with admixtures of such drugs, and the literature is reviewed relative to recent developments in hospital pharmacy departments where reconstitution of anticancer drugs has been incorporated into existing intravenous fluid preparation/admixture units. Not only has this been shown to be safer and more effective in terms of time and labor, but also it has cut the cost of injectable cytotoxic drugs by an

  10. Synthesis and serotonin transporter activity of 1,3-bis(aryl)-2-nitro-1-propenes as a new class of anticancer agents

    DEFF Research Database (Denmark)

    McNamara, Yvonne M.; Cloonan, Suzanne M.; Knox, Andrew J.S.;

    2011-01-01

    Structural derivatives of 4-MTA, an illegal amphetamine analogue have been previously shown to have anticancer effects in vitro. In this study we report the synthesis of a series of novel 1,3-bis(aryl)-2-nitro-1-propene derivatives related in structure to 4-MTA. A number of these compounds...

  11. Histone deacetylase inhibitors (HDACIs: multitargeted anticancer agents

    Directory of Open Access Journals (Sweden)

    Ververis K

    2013-02-01

    Full Text Available Katherine Ververis,1 Alison Hiong,1 Tom C Karagiannis,1,* Paul V Licciardi2,*1Epigenomic Medicine, Alfred Medical Research and Education Precinct, 2Allergy and Immune Disorders, Murdoch Childrens Research Institute, Melbourne, VIC, Australia*These authors contributed equally to this workAbstract: Histone deacetylase (HDAC inhibitors are an emerging class of therapeutics with potential as anticancer drugs. The rationale for developing HDAC inhibitors (and other chromatin-modifying agents as anticancer therapies arose from the understanding that in addition to genetic mutations, epigenetic changes such as dysregulation of HDAC enzymes can alter phenotype and gene expression, disturb homeostasis, and contribute to neoplastic growth. The family of HDAC inhibitors is large and diverse. It includes a range of naturally occurring and synthetic compounds that differ in terms of structure, function, and specificity. HDAC inhibitors have multiple cell type-specific effects in vitro and in vivo, such as growth arrest, cell differentiation, and apoptosis in malignant cells. HDAC inhibitors have the potential to be used as monotherapies or in combination with other anticancer therapies. Currently, there are two HDAC inhibitors that have received approval from the US FDA for the treatment of cutaneous T-cell lymphoma: vorinostat (suberoylanilide hydroxamic acid, Zolinza and depsipeptide (romidepsin, Istodax. More recently, depsipeptide has also gained FDA approval for the treatment of peripheral T-cell lymphoma. Many more clinical trials assessing the effects of various HDAC inhibitors on hematological and solid malignancies are currently being conducted. Despite the proven anticancer effects of particular HDAC inhibitors against certain cancers, many aspects of HDAC enzymes and HDAC inhibitors are still not fully understood. Increasing our understanding of the effects of HDAC inhibitors, their targets and mechanisms of action will be critical for the

  12. In Vitro Resistance Development to Nemonoxacin in Streptococcus pneumoniae: A Unique Profile for a Novel Nonfluorinated Quinolone

    Science.gov (United States)

    Roychoudhury, Siddhartha; Makin, Kelly; Twinem, Tracy; Leunk, Robert

    2016-01-01

    Selection of resistant strains in Streptococcus pneumoniae was studied in vitro with nemonoxacin, a novel nonfluorinated quinolone (NFQ), in comparison with quinolone benchmarks, ciprofloxacin, garenoxacin, and gatifloxacin. In stepwise resistance selection studies, a 256-fold loss of potency was observed after three to four steps of exposure to ciprofloxacin or garenoxacin. In contrast, the loss of potency was limited to eightfold after three steps of exposure to nemonoxacin and repeated attempts to isolate highly resistant organisms after four steps of exposure yielded isolates that could not be subcultured in liquid medium. The quinolone resistance-determining regions of the target genes, parC, parE, gyrA, and gyrB, were analyzed through DNA sequencing. Known mutations, especially in the hotspots of parC and gyrA, were selected with exposure to garenoxacin, ciprofloxacin, and gatifloxacin. In contrast, mutations selected with nemonoxacin were limited to GyrA, GyrB, and ParE, sparing ParC, which is known as a key driver of resistance in clinical isolates of S. pneumoniae. This observation is consistent with previous data using other NFQs, which showed no loss of potency due to ParC mutations in clinical isolates. This apparently unique feature of nemonoxacin is potentially attributable to the structural uniqueness of the NFQs, distinguishing them from the fluoroquinolones that are commonly prescribed for infections by S. pneumoniae. PMID:27267788

  13. Hydroxamic acid - A novel molecule for anticancer therapy

    Directory of Open Access Journals (Sweden)

    Dilipkumar Pal

    2012-01-01

    Full Text Available Hydroxamic acid is a potent moiety not only in the field of cancer therapy but also as a mutagenic agent. Among the various derivatives of hydroxamic acid, SAHA (Suberoylanilide Hydroxamic Acid is considered as a potent anticancer agent. Scientists from the different corner synthesized different hydroxamic acid moieties with some straight chain oxazole, thiadiazole, biphenyl moieties in the terminal position. Acetylation and deacetylation of histones of the core proteins of nucleosomes in chromatin play an important role in the regulation of gene expression. The level of acetylation of histones is established and maintained by two classes of enzymes, histone acetyltransferase and histone deacetylases, which have been identified as transcriptional coactivators and transcriptional corepressors, respectively. There is increasing evidence that aberrant histone acetylation has been linked to various malignant diseases. Great efforts are currently underway for the design of more potent and less toxic candidates for the treatment of cancer. In recent years, hydroxamic acid derivatives have attracted increasing attention for their potential as highly efficacious in combating various etiological factors associated with cancer. Our main intention to draw an attention is that this single functional moiety has not only fit in the receptor but also create a diversified activity.

  14. ANTICANCER ACTIVITY OF ISOLATED CHEMICAL CONSTITUENTS FROM MILIUSA SMITHIAE

    Directory of Open Access Journals (Sweden)

    Chonthicha Naphong

    2013-01-01

    Full Text Available Miliusa plants belonging to the family Annonaceae are found in Thailand and have been used as Thai traditional medicines. There have been a few previously reports on the chemical constituents of plants in this genus, describing the presence of aporphine alkaloids, terpenoids, flavonoids, phenylpropanoids, styrylpyrones, bis-styryls and homogentisic acid derivatives. Miliusa smithiae, a new species for Thailand and world, has not been studied chemical composition. The present study described phytochemical study of the leaves and twigs of M. smithiae together with their cytotoxicity. The M. smithiae was selected and percolated with hexane, ethyl acetate, acetone and methanol. The extracts were purified and elucidated chemical structures. The constituent of ethyl acetate extract of M. smithiae has been investigated. We isolated and identified two flavonoid derivatives, 5-hydroxy-3,7,4′-trimetoxyflavone (1 and 5,3′-dihydroxy-3,7,4′-trimetoxyflavone (2. The structures of these compounds were elucidated on the basis of spectroscopic evidence. Studies on ethyl acetate extract of M. smithiae has now resulted the isolation and structural characterization of two flavonoids. Their anticancer activities were evaluated using SRB assays. In this method, compound 2 showed potential activity in cell lines.

  15. Discovery and development of natural product oridonin-inspired anticancer agents.

    Science.gov (United States)

    Ding, Ye; Ding, Chunyong; Ye, Na; Liu, Zhiqing; Wold, Eric A; Chen, Haiying; Wild, Christopher; Shen, Qiang; Zhou, Jia

    2016-10-21

    Natural products have historically been, and continue to be, an invaluable source for the discovery of various therapeutic agents. Oridonin, a natural diterpenoid widely applied in traditional Chinese medicines, exhibits a broad range of biological effects including anticancer and anti-inflammatory activities. To further improve its potency, aqueous solubility and bioavailability, the oridonin template serves as an exciting platform for drug discovery to yield better candidates with unique targets and enhanced drug properties. A number of oridonin derivatives (e.g. HAO472) have been designed and synthesized, and have contributed to substantial progress in the identification of new agents and relevant molecular mechanistic studies toward the treatment of human cancers and other diseases. This review summarizes the recent advances in medicinal chemistry on the explorations of novel oridonin analogues as potential anticancer therapeutics, and provides a detailed discussion of future directions for the development and progression of this class of molecules into the clinic.

  16. A Novel Class of Emerging Anticancer Compounds: Oxyprenylated Secondary Metabolites from Plants and Fungi.

    Science.gov (United States)

    Genovese, Salvatore; Fiorito, Serena; Epifano, Francesco; Taddeo, Vito Alessandro

    2015-01-01

    O-Prenyl secondary metabolites (3,3-dimethylallyl, geranyl-, farnesyl- and related biosynthetic derivatives) represent a class of rarely occurring natural products. In the last two decades such compounds have been found to exert promising and effective pharmacological activities, mainly in terms of anti-cancer properties. To date about 350 oxyprenylated secondary metabolites, the most part of which having a phenylpropanoid or a polyketide core, have been extracted from plants mainly belonging to the Rutaceae, Apiaceae, and Fabaceae families, and from fungi and bacteria. The aim of this comprehensive review is to make a survey of the in so far reported literature citations about O-prenyl secondary metabolites exhibiting in vitro and in vivo anti-cancer properties from phytochemical and pharmacological point of views.

  17. Secondary metabolites as DNA topoisomerase inhibitors: A new era towards designing of anticancer drugs

    Directory of Open Access Journals (Sweden)

    Supriya Baikar

    2010-01-01

    Full Text Available A large number of secondary metabolites like alkaloids, terpenoids, polyphenols and quinones are produced by the plants. These metabolites can be utilized as natural medicines for the reason that they inhibit the activity of DNA topoisomerase which are the clinical targets for anticancer drugs. DNA topoisomerases are the cellular enzymes that change the topological state of DNA through the breaking and rejoining of DNA strands. Synthetic drugs as inhibitors of topoisomerases have been developed and used in the clinical trials but severe side effects are a serious problem for them therefore, there is a need for the development of novel plant-derived natural drugs and their analogs which may serve as appropriate inhibitors with respect to drug designing. The theme for this review is how secondary metabolites or natural products inactivate the action of DNA topoisomerases and open new avenues towards isolation and characterization of compounds for the development of novel drugs with anticancer potential.

  18. Hierarchical targeted hepatocyte mitochondrial multifunctional chitosan nanoparticles for anticancer drug delivery.

    Science.gov (United States)

    Chen, Zhipeng; Zhang, Liujie; Song, Yang; He, Jiayu; Wu, Li; Zhao, Can; Xiao, Yanyu; Li, Wei; Cai, Baochang; Cheng, Haibo; Li, Weidong

    2015-06-01

    The overwhelming majority of drugs exert their pharmacological effects after reaching their target sites of action, however, these target sites are mainly located in the cytosol or intracellular organelles. Consequently, delivering drugs to the specific organelle is the key to achieve maximum therapeutic effects and minimum side-effects. In the work reported here, we designed, synthesized, and evaluated a novel mitochondrial-targeted multifunctional nanoparticles (MNPs) based on chitosan derivatives according to the physiological environment of the tumor and the requirement of mitochondrial targeting drug delivery. The intelligent chitosan nanoparticles possess various functions such as stealth, hepatocyte targeting, multistage pH-response, lysosomal escape and mitochondrial targeting, which lead to targeted drug release after the progressively shedding of functional groups, thus realize the efficient intracellular delivery and mitochondrial localization, inhibit the growth of tumor, elevate the antitumor efficacy, and reduce the toxicity of anticancer drugs. It provides a safe and efficient nanocarrier platform for mitochondria targeting anticancer drug delivery.

  19. International Conference on Harmonisation; Guidance on S9 Nonclincal Evaluation for Anticancer Pharmaceuticals; availability. Notice.

    Science.gov (United States)

    2010-03-08

    The Food and Drug Administration (FDA) is announcing the availability of a guidance entitled "S9 Nonclinical Evaluation for Anticancer Pharmaceuticals." The guidance was prepared under the auspices of the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH). The guidance provides recommendations for nonclinical studies for the development of pharmaceuticals, including both drugs and biotechnology derived products, intended to treat patients with advanced cancer. The recommendations describe the type and timing of nonclinical studies to support an investigational new drug application (IND) and the submission of a new drug application (NDA) or biologics license application (BLA). The guidance is intended to provide information on internationally accepted recommendations for nonclinical studies to facilitate the development of anticancer pharmaceuticals.

  20. Quinolone co-resistance in ESBL- or AmpC-producing Escherichia coli from an Indian urban aquatic environment and their public health implications.

    Science.gov (United States)

    Bajaj, Priyanka; Kanaujia, Pawan Kumar; Singh, Nambram Somendro; Sharma, Shalu; Kumar, Shakti; Virdi, Jugsharan Singh

    2016-01-01

    Quinolone and β-lactam antibiotics constitute major mainstay of treatment against infections caused by pathogenic Escherichia coli. Presence of E. coli strains expressing co-resistance to both these antibiotic classes in urban aquatic environments which are consistently being used for various anthropogenic activities represents a serious public health concern. From a heterogeneous collection of 61 E. coli strains isolated from the river Yamuna traversing through the National Capital Territory of Delhi (India), those harboring blaCTX-M-15 (n = 10) or blaCMY-42 (n = 2) were investigated for co-resistance to quinolones and the molecular mechanisms thereof. Resistance was primarily attributed to amino acid substitutions in the quinolone resistance-determining regions (QRDRs) of GyrA (S83L ± D87N) and ParC (S80I ± E84K). One of the E. coli strains, viz., IPE, also carried substitutions in GyrB and ParE at positions Ser492→Asn and Ser458→Ala, respectively. The phenotypically susceptible strains nevertheless carried plasmid-mediated quinolone resistance (PMQR) gene, viz., qnrS, which showed co-transfer to the recipient quinolone-sensitive E. coli J53 along with the genes encoding β-lactamases and led to increase in minimal inhibitory concentrations of quinolone antibiotics. To the best of our knowledge, this represents first report of molecular characterization of quinolone co-resistance in E. coli harboring genes for ESBLs or AmpC β-lactamases from a natural aquatic environment of India. The study warrants true appreciation of the potential of urban aquatic environments in the emergence and spread of multi-drug resistance and underscores the need to characterize resistance genetic elements vis-à-vis their public health implications, irrespective of apparent phenotypic resistance.